Renting a car is definitely recommended for those who plan to move beyond their hotel beach chair. Public transportation is extremely limited, and you may want a car if you plan to explore or if you have time constraints.

Remember that Hawai'i residents refer to places as being either mauka (toward the mountains) or makai (toward the ocean) from one another. Other directions depend on your location: in Honolulu, for example, people say to "go Diamond Head," which means toward that famous landmark, or to "go 'ewa," meaning in the opposite direction.

Hawai'i's natural beauty, breathtaking coastal routes, and year-round fair weather make it attractive to explore by bike. However, on many roads, bicycle lanes are limited or nonexistent, and cyclists must contend with heavy traffic on the more populated islands. Bike routes on the Big Island include the challenge of riding the 225-mi circle-island route. You can rent bikes for some solo cruising, join local cycling clubs for their weekly rides, or hit the road with outfitters for tours that go beyond the well-traveled paths.

Bike maps are available from the Big Island Mountain Bike Association (PHONE: 808/961-4452).

There are several rental shops in Kailua-Kona and a couple in Waimea and Hilo. Resorts rent bicycles that can be used around the properties.

B&L Bike and Sports (75-5699 Kopiko Pl., Kailua-Kona. PHONE: 808/329-3309), in downtown Kailua-Kona, rents various bikes, with prices for mountain bikes starting around $30 for 24 hours.

Upcountry, close to trails that flank the slopes of Mauna Kea, C&S Outfitters (64-1066 Mamalahoa Hwy., Waimea. PHONE: 808/885-5005) has both road and mountain bikes.

Dave's Bike & Triathlon Shop (75-5669 Ali'i Dr., Kailua-Kona. PHONE: 808/329-4522) specializes in road and race bikes.

Hawaiian Pedals (Kona Inn Shopping Village, 75-5744 Ali'i Dr., HI, USA. PHONE: 808/329-2294) rents road and mountain bikes, starting at $15 for five hours or $20 for the whole day.

Hilo Bike Hub (318 E. Kawili St., Hilo. PHONE: 808/961-4452) caters to bike enthusiasts ready to explore Volcano and its surroundings.

Experienced riders will find rugged mountain bikes at HP BikeWorks (74-5599 Luhia St., Suite F-3, Kailua-Kona. PHONE: 808/326-2453) for $25 a day for front-suspension bikes and $30 a day for full-suspension bikes.

At the Hilton Waikoloa Village, Red Sail Sports (425 Waikoloa Beach Dr., Waikoloa. PHONE: 808/886-2876) rents out bikes to guests of the resort for $7 per hour or $20 for the whole day.

Hele-On Bus (PHONE: 808/961-8744, www.hawaii-county.com/mass_transit/transit_main.htm) operates Monday through Saturday between Hilo and Kailua-Kona, for $5.25 each way or $7 round-trip. The once-daily connection takes about three hours each way and stops in numerous locations. An additional $1 is charged for luggage and backpacks that do not fit under the seat. The Hele-On operates in the Hilo and Kailua-Kona town areas themselves for 75¢ and up; exact fare is required. The bus also services the regions of North Kohala, Waimea, and Ka'u. The county Web site shows complete schedules, additional services, and fees.

The Ali'i Shuttle (PHONE: 808/938-1112) operates a bus service in the Kona resort area between Keauhou Bay and Kailua-Kona town Monday through Saturday, 8:30 AM to 7 PM. The shuttle connects all major hotels, condos, attractions, and shopping centers along Ali'i Drive. The cost is $3.

You need a car to see the sights of the Big Island in any reasonable amount of time. Even if you're solely interested in relaxing at your self-contained megaresort, you may still want to rent a car, simply to travel to Kailua-Kona or to the restaurants in Waimea.

Though there are several car-rental companies from which to choose, cars can be scarce during holiday weekends, special events, and peak seasons -- from mid-December through mid-March. It is best to book well in advance.

If you rent a car, be sure to get a "Drive Guide." These handy booklets have all the maps you'll probably need to navigate the island.

Regardless of today's fluctuating gas prices, you can pretty much count on having to pay more at the pump for gasoline in the Islands than on the U.S. mainland.

Car Rentals

Rates on the Big Island begin at about $40 a day for an economy car with air-conditioning, automatic transmission, and unlimited mileage. A $3-per-day road tax is also assessed on each rental vehicle.To get the best rate on a rental car, book it in conjunction with an interisland Hawaiian or Aloha Airlines flight, or ask your travel agent to check out room-and-car packages. Note that dropping off a rental at a different airport from where you originally rented may cost you as much as $85 extra.

Two companies on the island rent RVs. Island RV gives you a ready-to-go vacation that includes a complete itinerary, equipment rentals, and customized care; Harper Rentals just gets you the RV as is. Linens are available at both outfits.

On the Big Island

Alamo (PHONE: 800/327-9633).

Avis (PHONE: 800/321-3712).

Budget (PHONE: 800/527-0700).

Dollar (PHONE: 800/800-4000).

Enterprise (PHONE: 800/736-8222).

Harper Car and Truck Rental (PHONE: 808/969-1478 or 800/852-9993, www.harperhawaii.com).

Hertz (PHONE: 800/654-3011).

Island RV (PHONE: 808/334-0464 or 800/406-4555, www.islandrv.com).

National (PHONE: 800/227-7368).

Thrifty (PHONE: 800/367-2277).

At Home

Alamo (PHONE: 800/327-9633; 020/8759-6200 in the United Kingdom, www.alamo.com).

Avis (PHONE: 800/331-1212; 800/879-2847 in Canada; 02/9353-9000 in Australia; 09/525-1982 in New Zealand, www.avis.com).

Budget (PHONE: 800/527-0700; 0144/227-6266 in the United Kingdom, www.budget.com).

Dollar (PHONE: 800/800-4000; 020/8897-0811 in the United Kingdom; 02/9223-1444 in Australia, www.dollar.com).

Enterprise (PHONE: 800/325-8007, www.enterprise.com).

Hertz (PHONE: 800/654-3131; 800/263-0600 in Canada; 020/8897-2072 in the United Kingdom; 02/9669-2444 in Australia, www.hertz.com).

National (PHONE: 800/227-7368; 0345/222525 in the United Kingdom, www.nationalcar.com).

Thrifty (PHONE: 800/367-2277, www.thrifty.com).

Requirements

In Hawai'i you must be 21 years of age to rent a car and you must have a valid driver's license and a major credit card. Your unexpired mainland driver's license is valid for rental for up to 90 days. Those under 25 will pay a daily surcharge.

When picking up a rental car, non-U.S. residents need a reservation voucher for any prepaid reservations that were made in the traveler's home country, a passport, a driver's license, and a travel policy that covers each driver.

Road Conditions

It's difficult to get lost in most of Hawai'i. Roads and streets, although they may challenge the visitor's tongue, are well marked. Keep an eye open for the Hawai'i Visitors and Convention Bureau's red-caped King Kamehameha signs, which mark major attractions and scenic spots.

Most agencies make you sign an agreement that you won't drive on Saddle Road between Hilo and Waimea: it's a bumpy route that can be dangerous, and there are no petrol stations or emergency phones. On the other hand, if you're thinking about stargazing, you'll have to take the road up to Mauna Kea off Saddle Road for the clearest views. Alamo, Budget, Dollar, and Harper Rentals let you do this in their four-wheel-drive vehicles. You might consider a four-wheel-drive vehicle anyway to reach rugged shoreline sights.

Rules of the Road

Be sure to buckle up. Hawai'i has a strictly enforced seat-belt law for front-seat passengers. Children under 40 pounds must be in a car seat, available from your car-rental agency. Children 18 and under, riding in the backseat, are also required by state law to use seat belts.

The highway speed limit is usually 55 mph. In-town traffic moves from 25 to 40 mph. Jaywalking is very common, so be particularly watchful for pedestrians, especially in congested areas such as Waikiki. Unauthorized use of a parking space reserved for persons with disabilities can net you a $150 fine.

Scooters and motorcycles can be rented in Hilo and Kailua-Kona. Some words of warning: Big Island roads often have narrow shoulders, and the drafts from oversize tour buses swooping by can unexpectedly double the excitement of a simple Sunday ride. Helmets are advised but not mandatory in Hawai'i.

DJ's Rentals (75-5563A Palani Rd., Kailua-Kona. PHONE: 808/329-1700 or 800/993-4647).

Hilo Harley Davidson (100 Kanoelehua Ave., Hilo. PHONE: 808/934-9090).

Kona Harley Davidson (74-5615 Luhia St., Kailua-Kona. PHONE: 808/326-9887).

Several companies advertise guided tours by taxi, but it is an expensive way to travel, with a trip around the island totaling about $350.

Even people in paradise have to work. Generally local business hours are weekdays 8-5. Banks are usually open Monday-Thursday 8:30-3 and until 6 on Friday. Some banks have Saturday-morning hours.

Many self-serve petrol stations stay open around-the-clock, with full-service stations usually open from around 7 AM until 9 PM. U.S. post offices are open weekdays 8:30 AM-4:30 PM and Saturday 8:30-noon.

Museums and Sights

Most museums generally open their doors between 9 AM and 10 AM and stay open until 5 PM Tuesday-Saturday. Many museums operate with afternoon hours only on Sunday and close on Monday. Visitor-attraction hours vary throughout the state, but most sights are open daily with the exception of major holidays such as Christmas. Check local newspapers upon arrival for attraction hours and schedules if visiting over holiday periods. The local dailies carry a listing of "What's Open/What's Not" for those time periods.

Shops

Stores in resort areas sometimes open as early as 8, with shopping-center opening hours varying from 9:30 to 10 on weekdays and Saturday, a bit later on Sunday. Bigger malls stay open until 9 weekdays and Saturday and close at 5 on Sunday. Boutiques in resort areas may stay open as late as 11.

In Hawai'i

Plants and plant products are subject to regulation by the Department of Agriculture, both on entering and leaving Hawai'i. Upon leaving the Islands, you'll have to have your bags X-rayed and tagged at one of the airport's agricultural inspection stations before you proceed to check-in. Pineapples and coconuts with the packer's agricultural inspection stamp pass freely; papayas must be treated, inspected, and stamped. All other fruits are banned for export to the U.S. mainland. Flowers pass except for gardenia, rose leaves, jade vine, and mauna loa. Also banned are insects, snails, soil, cotton, cacti, sugarcane, and all berry plants.

You'll have to leave dogs and other pets at home. A strict six-month quarantine is imposed to keep out rabies, which is nonexistent in Hawai'i.

Arriving in the United States

Non-U.S. residents ages 21 and older may import into the United States 200 cigarettes or 50 cigars or 2 kilograms of tobacco, 1 litre of alcohol, and gifts worth $100. Meat products, seeds, plants, and fruits are prohibited.

For additional information, contact the U.S. Customs Service (1300 Pennsylvania Ave. NW, Washington, DC, 20229, USA. PHONE: 202/354-1000, www. customs.gov, Customer Satisfaction Unit, 1300 Pennsylvania Ave. NW, Room 5.5A. Office of Passenger Programs, 1300 Pennsylvania Ave. NW, Room 5.4D, PHONE: 202/927-0530).

The U.S. electrical standard is 110 volts/60 cycles AC. Foreign visitors traveling with dual-voltage appliances will not need a converter, but they will need a plug adapter. The standard U.S. electrical outlet takes a plug of two flat pins set parallel to one another.

Australia

Australian Consulate (1000 Bishop St., Honolulu, 96813. PHONE: 808/524-5050).

Australian Embassy (1601 Massachusetts Ave. NW, Washington, DC, 20036, USA. PHONE: 202/797-3000, FAX: 202/797-3040).

Canada

Canadian Consulate (1000 Bishop St., Honolulu, 96813. PHONE: 808/524-5050).

Canadian Embassy (501 Pennsylvania Ave. NW, Washington, DC, 20001, USA. PHONE: 202/682-1740, FAX: 202/682-7726).

New Zealand

New Zealand Consulate (900 Richards St., Room 414, Honolulu, 96813. PHONE: 808/543-7900).

New Zealand Embassy (37 Observatory Circle NW, Washington, DC, 20008, USA. PHONE: 202/328-4800, FAX: 202/667-5227).

United Kingdom

British Consulate (1000 Bishop St., Honolulu, 96813. PHONE: 808/524-5050).

British Embassy (3100 Massachusetts Ave. NW, Washington, DC, 20008, USA. PHONE: 202/588-7800, FAX: 202/588-7850).

Ambulance (PHONE: 911).

Fire (PHONE: 911).

Police (PHONE: 911 or 808/935-3311).

Poison Control Center (PHONE: 800/362-3585).

The Volcano Update Hotline (PHONE: 808/985-6000) provides 24-hour recorded information.

Hospitals

Hilo Medical Center (1190 Waianuenue Ave., Hilo. PHONE: 808/974-4700).

Kona Community Hospital (Hwy. 11 at Hau Kapila St., Kealakekua. PHONE: 808/322-9311).

Kona-Kohala Medical Associates (75-137 Hualalai Rd., Kailua-Kona. PHONE: 808/329-1346).

North Hawai'i Community Hospital (67-1125 Mamalahoa Hwy., Waimea. PHONE: 808/885-4444).

Airplane & Helicopter Tours

There's nothing quite like gazing at a waterfall that drops a couple of thousand feet into multiple pools. You can also fly above the lava lake on Kilauea, then follow the flow to the ocean, where clouds of steam billow into the air. (The lava flow has been changing locations and sometimes goes underground, so ask exactly what you'll see when you book your flight.) For a fee, some tour companies will record your flight as a souvenir if you wish. You can go in small planes that carry three to nine passengers or helicopters that carry up to six passengers. Expect to pay anywhere from $150 for 50-minute flights to $325-plus for two hours, and make reservations in advance.

Big Island Air (Kona International Airport, HI, USA. PHONE: 808/329-4868 or 800/303-8868) offers plane tours.

Blue Hawaiian Helicopters (Hilo International Airport or Waikoloa Helipad, HI, USA. PHONE: 808/961-5600 or 800/786-2583, www.bluehawaiian.com) offers helicopter tours.

Island Hoppers Hawai'i (Hilo and Kona International Airports, HI, USA. PHONE: 808/969-2000 or 800/538-7590, www.fly-hawaii.com/above) offers plane tours. They leave from Hilo airport for 50-minute flights and from Kailua-Kona for 2- and 2½-hour flights.

Sunshine Helicopters (Helipad at the Hapuna Beach Prince Hotel and Hilo International Airport, HI, USA. PHONE: 808/882-1223 or 800/622-3144, www.sunshinehelicopters.com) offers helicopter tours.

Tropical Helicopters (Hilo International Airport, HI, USA. PHONE: 808/961-6810, www.tropicalhelicopters.com) offers helicopter tours.

Volcano Helicopters (Hilo International Airport, HI, USA. PHONE: 808/961-3355) offers helicopter tours.

All-Terrain-Vehicle Tours

A different way to experience the Big Island's rugged coastline and wild ranch lands is through an off-road adventure. At higher elevations, weather can be nippy and rainy, but views can be awesome. You can ride in your own all-terrain vehicle or share a Hummer. Protective gear is provided. Prices range from $85 to $125 per person, depending on tour length and specifics.

ATV Outfitters Hawai'i (Old Sakamoto Store, Hwy. 270, Kapa'au. PHONE: 808/889-6000 or 888/288-7288, www.outfittershawaii.com).

Bedrock Ranch ATV Adventure (Hwy. 11, Ka'u District, Waiohinu. PHONE: 808/929-8157, www.bedrockranchatv.com).

HMV Tours (Hwy. 250, Hawi. PHONE: 808/889-6922 or 877/449-6922, www.hmvtours.com).

Kahua Ranch ATV Rides (Hwy. 250, 10 mi north of Waimea, HI, USA. PHONE: 808/882-7954 or 808/882-4646, www.kahuaranch.com).

Kukui ATV & Adventures (Pickup from Waipi'o Valley Artworks, Kukuihaele, HI, USA. PHONE: 808/775-1701 or 877/757-1414, www.topofwaipio.com).

Boat Tours

A voyage on a traditional double-hulled sailing canoe is available on the Hahalua Lele (PHONE: 808/885-2000, www.fairmont.com) along the Kohala shores near the Fairmont Orchid Hawai'i. The crew spices up the tour with Hawaiian history and legends. Expect to pay $100.

Unique among the abundance of water adventures is the Atlantis IV Submarine (PHONE: 808/329-6626 or 800/548-6262, www.atlantisadventures.com) one-hour tour from Kailua Pier, across from King Kamehameha's Kona Beach Hotel in Kona. A large glass dome in the bow and 13 viewing ports on the sides allow clear views of the watery world. Children must be at least 3 ft tall. Fees for adults range from $75 to $90.

Bus Tours

Local tour-bus operators conduct volcano tours and circle-island tours, with pickup at the major resorts. Costs range from $38 to $68, depending on pickup location.

Jack's Tours (PHONE: 808/886-2202 in Kona; 808/961-6666 in Hilo; 800/442-5557).

Polynesian Adventure Tours (PHONE: 808/329-8008 in Kona; 800/622-3011, www.polyad.com).

Roberts Hawai'i (PHONE: 808/329-1688 in Kona; 808/966-5483 in Hilo; 800/831-5541, www.robertshawaii.com).

Coffee-Farm Tours

Several coffee farms around the South Kona and Upcountry Kona coffee-belt area from Holualoa to Honaunau welcome visitors. You'll learn about the whole process, from green beans to packaging. Often, macadamia nuts are for sale, and the brew, of course, is always ready. Some tours are self-guided, and most are free.

Bay View Farms (Honaunau. PHONE: 808/328-9658).

Greenwell Farms (81-6581 Mamalahoa Hwy., Kealakekua. PHONE: 808/323-2862).

Holualoa-Kona Coffee Company (77-6261 Old Mamalahoa Hwy., (Hwy. 180), Holualoa. PHONE: 808/322-9937 or 800/334-0348).

Royal Kona Coffee Museum and Coffee Mill (83-5427 Mamalahoa Hwy., next to tree house in Honaunau, HI, USA. PHONE: 808/328-2511).

The Kona Coffee Living History Farm (known as the D. Uchida Farm, Kona Historical Society, 81-6551 Mamalahoa Hwy., Kealakekua. PHONE: 808/323-3222, www.konahistorical.org) is unique in its heritage of coffee pioneers. The site, which has been preserved and restored by the Kona Historical Society, includes a 1913 farmhouse surrounded by coffee trees, a Japanese bathhouse, Kuriba (coffee processing mill), and Hoshidana (traditional drying platform). Tours of the farm are available by reservation only and cost $20.

Garden Tours

Several botanical gardens across the island welcome you to meander along the trails and study the diversity of the local flora.

Often overlooked is the Amy B. H. Greenwell Ethnobotanical Garden (82-6188 Maalahoa Hwy., Captain Cook. PHONE: 808/323-3318, www.bishopmuseum.org/greenwell), with its wealth of Hawaiian cultural traditions. It has on 12 acres 250 types of plants, including food and fiber crops, that were typical in an early Hawaiian ahupua'a, a pie-shape land division that ran from the mountains to the sea. Call to find out about guided tours or drop in between 8:30 AM and 5 PM.

Mauna Kea Astronomy Tours

On the weekend, the Onizuka Center for International Astronomy Visitor Information Station (Summit Access Rd., HI, USA. PHONE: 808/961-2180, www.ifa.hawaii.edu/info/vis) offers an escorted summit tour using four-wheel-drive vehicles. Departure is at 1 PM, and reservations are not required. You must be 16 or older, in good health, and not pregnant.

As an easier alternative, book a tour with a reliable company. Tour operators usually provide parkas, as well as telescopes, snacks, and meals when appropriate. They pick you up at convenient locations, including the resorts. Excursion fees range from about $75 to $155.

Arnott's Lodge & Hiking Adventures (PHONE: 808/969-7097, www.arnottslodge.com).

Hawai'i Forest & Trail (PHONE: 808/331-8505 or 800/464-1993, www.hawaii-forest.com).

Paradise Safaris (PHONE: 808/322-2366 or 888/322-2366, www.maunakea.com).

Ranch Tours

Three historic, working ranches have opened their lands to guided activities.

The verdant Kohala Mountains land stretches down to the sea from the rim of Pololu Valley high in the rain forest and holds legendary stories about King Kamehameha and his troops. Here, the owners of the 8,000-plus acres of Kahua Ranch (Kahua Ranch, Hwy. 250, HI, USA. PHONE: 808/882-7954 or 808/882-4646, www.kahuaranch.com) -- known for its lamb, beef, and hydroponic vegetables -- provide horseback riding, operations tours, ATV adventures, mountain biking, hiking, and clay shooting. There is even a guest house.

Paniolo Riding Adventures (Hwy. 250, close to mile marker 13, Kohala Mountain Rd., HI, USA. PHONE: 808/889-5354, www.panioloadventures.com) offers horseback rides, mountain-bike tours, and guided hikes in Ponoholo Ranch, an 11,000-acre cattle ranch that shelters prehistoric sites and ancient ruins.

A covered wagon pulled by a pair of draft horses leads you through a portion of the 225,000-acre Parker Ranch (Parker Ranch Visitor Center, Hwy. 19, Waimea. PHONE: 808/885-7655, www.parkerranch.com). If you are a reasonably experienced horseback rider, you can also participate in a two-hour trek that includes a cattle drive. Hiking tours and other adventures are available as well.

Valley Tours

Although you certainly can hike down into the Waipi'o and Pololu valleys that frame the Kohala Mountains, a horseback-riding tour might be more fun. Or consider a guided tour around Waipi'o rim by a four-wheel-drive vehicle and around Pololu by mule. You'll be treated to breathtaking views along historic trails, and experienced guides are happy to recount the ancient history of this land. Costs range from about $40 to $85.

Four-Wheel, Wagon, Shuttle Tours

Waipi'o Rim Backroad Adventures (PHONE: 808/775-1122 or 877/757-1414, www.topofwaipio.com).

Waipi'o Valley Shuttle (PHONE: 808/775-7121).

Waipi'o Valley Wagon Tours (PHONE: 808/775-9518).

Horseback Riding Tours

Waipi'o on Horseback (PHONE: 808/775-7291).

Waipi'o (Na'alapa) Stables (PHONE: 808/775-0419).

Mule Tours

Hawai'i Forest and Trail (PHONE: 808/331-8505 or 800/464-1993, www.hawaii-forest.com).

Walking & Hiking Tours

Maps and brochures for self-guided walking tours in historic areas or parks are often available on-site or at locations listed below. In Kailua-Kona, interpretive guides from the Kona Historical Society conduct various guided tours for a small fee.

As for nature hikes, to get to some of the best trails and places, it's worth going with a skilled guide. Costs range from $75 to $180, and hikes include picnic meals and gear such as binoculars, ponchos, and walking sticks. The outfitters mentioned here also offer customized adventure tours. Expert naturalist guides from Hawai'i Forest and Trail take you to 500-ft Kalopa Falls in North Kohala and on bird-watching expeditions. They, as well as Hawai'i Volcanoes National Park rangers, also offer tours into lava tubes and through normally inaccessible areas of Hawai'i Volcanoes National Park and rain forests. Hawaiian Walkways conducts several tours -- waterfall hikes, coastal adventures, flora and fauna explorations, and jaunts through Hawai'i Volcanoes National Park -- as well as custom-designed trips.

Historic Tours

Big Island Visitors Bureau (250 Keawe St., Hilo. PHONE: 808/961-5797, King's Shops, 250 Waikoloa Beach Dr., Suite B 15, Waikoloa, PHONE: 808/886-1655).

Kona Historical Society (81-6551 Mamalahoa Hwy., Kealakekua. PHONE: 808/323-3222, www.konahistorical.org).

Nature Hikes

Hawai'i Forest and Trail (PHONE: 808/331-8505 or 800/464-1993, www.hawaii-forest.com).

Hawai'i Volcanoes National Park (PHONE: 808/985-6010).

Hawaiian Walkways (PHONE: 808/775-0372 or 800/457-7759, www.hawaiianwalkways.com).

Whale-Watching Tours

Most Hawaiian whale-watching cruises focus on the migratory humpbacks that are seen here only from December through April. You can contact any one of the many snorkeling, scuba diving, sailing, and kayaking companies as well: in season they adapt their adventures.

Captain Dan McSweeney's Year-Round Whale Watching Adventures (Honokohau Harbor, Kailua-Kona. PHONE: 808/322-0028 or 888/942-5376, www.ilovewhales.com) offers three-hour trips year-round to find six other species of whales that rarely stray far from the Kona Coast. The cost is about $55.

Water-Sports Tours

You can sail, cruise the ocean, fish, and snorkel to your heart's content on the Big Island, but two unique water tours stand apart from the others.

Flumin' Da Ditch (55-519 Hawi Rd., (Hwy. 250), Hawi. PHONE: 808/889-6922 or 877/449-6922, www.flumindaditch.com) offers an $89 kayak adventure down the pitch-black, eerie tunnels of the 22½-mi Kohala Ditch -- irrigation ditches, built in 1905 by Japanese workers. You'll emerge now and then to pristine rain forests. "Flumin the ditch" in an inner tube used to be a dangerous and exciting pastime for sugar-plantation children.

The tour provided by Hawaiian Adventure Tours (Kapa'au. PHONE: 808/889-0227 or 800/659-3544, www.hawaiianadventuretours.com) is a land-and-water package that combines hiking, swimming, snorkeling, and kayaking in 7-day ($1,750) or 10-day ($2,100) adventures on two or three Islands.

Every address in the United States belongs to a specific zip-code district, and each zip code has five digits. Some addresses include a second sequence of four numbers following the first five numbers, but although this speeds mail delivery for large organizations, it is not necessary to use it. Each zip-code district has at least one post office, where you can buy stamps and aerograms, send parcels, or conduct other postal business.

Occasionally you may find small stamp-dispensing machines in airports, train stations, bus terminals, large office buildings, hotel lobbies, pharmacys, or grocery stores, but don't count on it. Most Americans go to the post office to buy their stamps, and the lines can be long.

Official mailboxes are either the stout, royal blue steel bins on city sidewalks or mail chutes on the walls of post offices or in large office buildings. A schedule posted on mailboxes and mail slots should indicate when the mail is picked up.

Sending Mail Home

First-class letters (one ounce or less) sent within the United States cost 37 cents; postcards are 23 cents. A one-ounce letter to Canada or Mexico takes a 60-cent stamp and a postcard 50 cents. Letters sent airmail to all other overseas destinations cost 80 cents for one ounce or less (this rate category is now called airmail letter-post, and surface mail is now called economy letter-post); airmail postcards to other overseas destinations cost 70 cents. For 70 cents, you can also buy an aerogram -- a pre-stamped sheet of lightweight blue paper that folds into its own envelope.

Receiving Mail

If you wish to receive mail while traveling in the United States, have it sent c/o General Delivery at the city's main post office (be sure to use the right zip code). It will be held there for up to 30 days. You must pick it up in person, and bring identification with you. American Express offices in the United States do not hold mail.

Many of the Islands' best attractions and activities, such as beaches and hiking, can be found in the form of natural beauty and cost nothing to view. You'll pay 50¢ for a daily newspaper, $1.50 to ride the bus anywhere on O'ahu, and from $45 on up to attend a lu'au. Large museums cost between $8 and $15 per entry; smaller ones can cost from $3 to $6.

ATMs

Automatic teller machines for easy access to cash are everywhere on the Islands. ATMs can be found in shopping centers, small convenience and grocery stores, inside hotels and resorts, as well as outside most bank branches. For a directory of locations, call 800/424-7787 for the MasterCard Cirrus Maestro network or 800/843-7587 for the Visa Plus network.

Currency

The basic unit of U.S. currency is the dollar, which is subdivided into 100 cents. Coins are the copper penny (1 cent) and four silver coins: the nickel (5 cents), the dime (10 cents), the quarter (25 cents), and the half-dollar (50 cents). Silver $1 coins and "golden" dollar coins (the latter introduced in 2000) are rarely seen in circulation. Paper money comes in denominations of $1, $5, $10, $20, $50, and $100. All these bills are the same size and green in color; they are distinguishable only by the dollar amount indicated on them and by pictures of various famous American people and monuments.

For the most favorable rates, change money through banks. Although fees charged for ATM transactions may be higher abroad than at home, Cirrus and Plus exchange rates are excellent, because they are based on wholesale rates offered only by major banks. You won't do as well at exchange booths in airports or rail and bus stations, in hotels, in restaurants, or in stores, although you may find their hours more convenient. To avoid lines at airport exchange booths, get a bit of local currency before you leave home.

In general, U.S. banks will not cash a personal check for you unless you have an account at that bank (it doesn't have to be at that branch). Only in major cities are large bank branches equipped to exchange foreign currencies. Therefore, it's best to rely on credit cards, cash machines, and traveler's checks to handle expenses while you're traveling.

Exchanging Money

In the United States, it is not as easy to find places to exchange currency as it is in European cities. In major international cities, such as New York and Los Angeles, currency may be exchanged at some bank branches, as well as at currency-exchange booths in airports and at foreign-currency offices such as American Express Travel Service and Thomas Cook (check local directories for addresses and phone numbers). The best strategy is to buy traveler's checks in U.S. dollars before you come to the United States; although the rates may not be as good abroad, the time saved by not having to search constantly for exchange facilities far outweighs any financial loss.

Money Orders, Funds Transfers

Any U.S. bank is equipped to accept transfers of funds from foreign banks. It helps if you can plan dates to pick up money at specific bank branches. Your home bank can supply you with a list of its correspondent banks in the United States.

If you have more time, and you have a U.S. address where you can receive mail, you can have someone send you a certified check, which you can cash at any bank, or a postal money order (for as much as $700, obtained for a fee of up to 85¢ at any U.S. post office and redeemable at any other post office). From overseas, you can have someone go to a bank to send you an international money order (also called a bank draft), which will cost a $15-$20 commission plus airmail postage. Always bring two valid pieces of identification, preferably with photos, to claim your money.

Taxes

There is a 4. 16% state sales tax on all purchases, including food. A hotel room tax of 7.25%, combined with the sales tax of 4%, equals an 11.25% rate added onto your hotel bill.

A $3-per-day road tax is also assessed on each rental vehicle.

Tipping

Tip cab drivers 15% of the fare. Standard tips for restaurants and bar tabs run from 15% to 20% of the bill, depending on the standard of service. Bellhops at hotels usually receive $1 per bag, more if you have bulky items such as bicycles and surfboards. Tip the hotel room maid $1 per night, paid daily. Tip doormen $1 for assistance with taxis; tips for concierge vary depending on the service. For example, tip more for "hard-to-get" event tickets or dining reservations.

Entering the United States

Visitor visas are not necessary for Canadian citizens, or for citizens of Australia and the United Kingdom who are staying fewer than 90 days. A valid passport, a return-trip ticket, and proof of financial solvency are required; you'll be asked to fill out the Visa Waiver Form, I-94W, upon entry. Travelers who plan to stay more than 90 days can apply for the appropriate visa at the United States embassy or consulates in their home country. Canadian citizens need valid identification but neither a passport nor a visa to enter the United States.

At Home

If you live in the U.K.:

U.S. Embassy Visa Information Line (PHONE: 09068/200-290 recorded visa information; 09055/444-546 operator service; both with per-minute charges) for U.S. visa information.

U.S. Embassy Visa Branch (5 Upper Grosvenor Sq., London, W1A 2JB.) for U.S. visa information; send a self-addressed, stamped envelope.

Contact the U.S. Consulate General (Queen's House, 14 Queen St., Belfast, BT1 6EQ, Northern Ireland. PHONE: 028/9032-8239, www.usembassy.org.uk) if you live in Northern Ireland.

Contact the United States Consulate General (MLC Centre, 19-29 Martin Pl., 59th floor, Sydney, NSW, 2000. PHONE: 02/9373-9200; 1902/941-641 fee-based visa-inquiry line, www.usis-australia.gov/index.html) if you live in Australia.

If you live in New Zealand:

Embassy of the United States (29 Fitzherbert Terr., Thorndon, Wellington. PHONE: 04/462-6000, usembassy.org.nz).

U.S. Consulate General (Citibank Bldg., 3rd floor, 23 Customs St. E, Auckland. PHONE: 09/303-2724, usembassy.org.nz).

Passport Offices

The best time to apply for a passport, or to renew your old one, is in fall or winter. Before any trip, check your passport's expiration date, and, if necessary, renew it as soon as possible.

Australian Citizens

Australian Passport Office (PHONE: 131-232, www.dfat.gov.au/passports).

Canadian Citizens

Passport Office (PHONE: 819/994-3500 or 800/567-6868, www.dfait-maeci.gc.ca/passport).

New Zealand Citizens

New Zealand Passport Office (PHONE: 04/494-0700 for information on how to apply; 04/474-8000; 0800/225-050 in New Zealand for information on applications already submitted, www.passports.govt.nz).

U.K. Citizens

London Passport Office (PHONE: 0870/521-0410, www.ukpa.gov.uk) for fees and documentation requirements and to request an emergency passport.

U.S. Citizens

National Passport Information Center (PHONE: 900/225-5674 calls are 35¢ per minute for automated service; $1.05 per minute for operator service, travel.state.gov/passport_services.html).

Hawai'i is generally a safe tourist destination, but it's still wise to follow the same common sense safety precautions you would normally follow in your own hometown. Hotel and visitor-center staff can provide information should you decide to head out on your own to more remote areas. Rental cars are magnets for break-ins, so don't leave any valuables in the car, not even in a locked trunk. Avoid poorly lighted areas, beach parks, and isolated areas after dark as a precaution.

When hiking, stay on marked trails, no matter how alluring the temptation might be to stray. Weather conditions can cause landscapes to become muddy, slippery, and tenuous, so staying on marked trails will lessen the possibility of a fall or getting lost.

Ocean safety is of the utmost importance when visiting an island destination. Don't swim alone, and follow the international signage posted at beaches that alerts swimmers to strong currents, man-of-war jellyfish, sharp coral, high surf, sharks, and dangerous shore breaks. At coastal lookouts along cliff tops, heed the signs indicating that waves can climb over the ledges. Check with lifeguards at each beach for current conditions, and if the red flags are up, indicating swimming and surfing are not allowed, don't go in. Waters that look calm on the surface can harbor strong currents and undertows, and not a few people who were just wading have been dragged out to sea.

Local Scams

Be wary of those hawking "too good to be true" prices on everything from car rentals to attractions. Many of these offers are just a lure to get you in the door for time-share presentations. When handed a flyer, read the fine print before you make your decision to participate.

Women in Hawai'i

Women traveling alone are generally safe in the Islands, but always follow the safety precautions you would use in any major destination. When booking hotels, request rooms closest to the elevator, and always keep your hotel-room door and balcony doors locked. Stay away from isolated areas after dark; camping and hiking solo are not advised. If you stay out late visiting nightclubs and bars, use caution when exiting night spots and returning to your lodging.

The country code for the United States is 1. The area code for the Big Island is 808.

All U.S. telephone numbers consist of 10 digits -- the three-digit area code, followed by a seven-digit local number. If you're calling a number from another area-code region, dial "1" then all 10 digits. If you're calling from a distance but within the same area code, dial "1" then the last seven digits. For calls within the same local calling area, just dial the seven-digit number. A map of U.S. area codes is printed in the front of most local telephone directories.

Four special prefixes, "800," "888," "877," and "900," are not area codes but indicators of particular kinds of service. "800," "888," and "877" numbers can be dialed free from anywhere in the country -- usually they are prepaid commercial lines that make it easier for consumers to obtain information, products, or services. The "900" numbers charge you for making the call and generally offer some kind of entertainment, such as horoscope readings, sports scores, or sexually suggestive conversations. These services can be very expensive, so know what you're getting into before you dial a "900" number.

Directory & Operator Information

For assistance from an operator, dial "0". To get a local or national telephone number, dial 411; in a few places it is necessary to dial 555-1212. If you want to charge a long-distance call to the person you're calling, call collect by dialing "0" instead of "1" before the 10-digit number, and an operator will come on the line to assist you (the party you're calling, however, has the right to refuse the call).

International Calls

International calls can be direct-dialed from most phones; dial 011, followed by the country code and then the local number (the front pages of many local telephone directories include a list of overseas country codes). To have an operator assist you, dial "0" and ask for the overseas operator. The country code for Australia is 61; New Zealand, 64; and the United Kingdom, 44. To reach Canada, dial 1 + area code + number.

Long-Distance Calls

Competitive long-distance carriers make calling within the United States relatively convenient and let you avoid hotel surcharges. By dialing an 800 number, you can get connected to the long-distance company of your choice.

For details, contact AT&T (PHONE: 800/225-5288), MCI (PHONE: 800/888-8000), or Sprint (PHONE: 800/366-2255).

Public Phones

The most common pay phone in operation today is the coin-operated type. To use one, pick up the receiver, deposit your money (the minimum amount is posted on the machine), wait for a steady tone before dialing, and then dial the number. An automated message will alert you to deposit more money, if needed.

Telephone-card phones, so popular elsewhere in the world, are becoming increasingly common. Grocery stores, newsstands, and other establishments sell the disposable phone cards, available in varying amounts from $5 and up. To activate the card, dial the code number and follow the instructions printed on the card.

You can find lots of information and brochures at the Big Island Visitors Bureau (BIVB) booths at Big Island airports and at the offices in Hilo and King's Shops.

Call the Weather Hot Line (PHONE: 808/961-5582) for daily reports.

Tourist Offices

Big Island Visitors Bureau (250 Keawe St., Hilo, 96720. PHONE: 808/961-5797, FAX: 808/961-2126, 250 Waikoloa Beach Dr., B12, King's Shops, Waikoloa, 96738, PHONE: 808/886-1655; www.bigisland.org.).

Destination Hilo (2109F Kaiwiki Rd., Hilo, 96720. PHONE: 808/935-5294).

Destination Kona Coast. Mailing address: Box 2850, Kailua-Kona, 96745. PHONE: 808/329-6748, www.destinationkonacoast.com.

Kohala Coast Resort Association (69-275 Waikoloa Beach Dr., Waikoloa, 96743. PHONE: 808/886-4915 or 800/318-3637, www.kkra.org).

At Home

Before you go, contact the Hawai'i Visitors & Convention Bureau (HVCB) (Waikiki Business Plaza, 2270 Kalakaua Ave., Suite 801, Honolulu, 96815. PHONE: 808/923-1811 or 800/464-2924, www. gohawaii.com) for general information on each island, free brochures that include an accommodations and car-rental guide, and an entertainment and dining listing containing one-line descriptions of bureau members. Take a virtual visit to Hawai'i on the Web, which can be most helpful in planning many aspects of your vacation. The HVCB site has a calendar section that allows you to see what local events are in place during the time of your stay.

In the U.K. contact the Hawai'i Visitors & Convention Bureau. Mailing address: Box 208, Sunbury, Middlesex, TW16 5RJ. PHONE: 020/8941-4009, www.gohawaii.com. Send a £2 check or postal order for an information pack.

Hawai'i Attractions Association (PHONE: 808/596-7733, www.hawaiiattractions.com).

Canadian travelers can contact Travel USA (PHONE: 905/890-5662; 800/268-3482 in Ontario).

In the United Kingdom, contact the United States Travel and Tourism Administration (Box 1EN, London, W1A 1EN. PHONE: 020/7495-4466).

Long days of sunshine and fairly mild year-round temperatures make Hawai'i an all-season destination. Most resort areas are at sea level, with average afternoon temperatures of 75°F-80°F during the coldest months of December and January; during the hottest months of August and September the temperature often reaches 90°F. Only at high elevations does the temperature drop into the colder realms, and only at mountain summits does it reach freezing.

Most travelers head to the Islands during winter. From mid-December through mid-April, visitors from the mainland and other areas covered with snow find Hawai'i's sun-splashed beaches and balmy trade winds appealing. This high season means that fewer travel bargains are available; room rates average 10%-15% higher during this season than the rest of the year.

Rainfall can be high in winter, particularly on the north and east shores of each island. Generally speaking, you are guaranteed sun and warm temperatures on the west and south shores no matter what time of year. The Big Island's northern section gets more annual rainfall than the rest of Hawai'i.

The following are the normal daily temperature ranges for the Big Island:

January 65-80°F (18 to 27°C); February 65-80°F (18-27°C); March 69-81°F (21-27°C); April 69-83°F (21-28°C); May 70-85°F (21-29°C); June 72-86°F (22-30°C); July 73-87°F (23-31°C); August 74-88°F (23-31°C); September 73-88°F (23-31°C); October 72-87°F (22-31°C); November 69-84°F (21-29°C); December 67-81°F (19-27°C).

Holidays

Major national holidays include New Year's Day (Jan. 1); Martin Luther King, Jr., Day (3rd Mon. in Jan.); President's Day (3rd Mon. in Feb.); Memorial Day (last Mon. in May); Independence Day (July 4); Labor Day (1st Mon. in Sept.); Thanksgiving Day (4th Thurs. in Nov.); Christmas Eve and Christmas Day (Dec. 24 and 25); and New Year's Eve (Dec. 31).

In addition, Hawai'i celebrates Prince Kuhio Day (Mar. 26), King Kamehameha Day (June 11), and Admission Day (3rd Fri. in Aug.). State, city, and county offices as well as many local companies are closed for business.