With a facade like a great temple, this celebrated treasure house is housed in a ponderously dignified Greco-Victorian building that makes for a suitably grand impression. Inside you'll find some of the greatest relics of humankind: the Elgin Marbles, the Rosetta Stone, the Sutton Hoo Treasure -- everything, it seems, but the Ark of the Covenant. Now 250 years old, the museum has undergone great changes to modernize and update many of the galleries. The focal point is the unmissable Great Court, a massive glass-roofed space, which highlights and reveals the museum's best-kept secret -- an inner courtyard, which, for more than 150 years had been used for storage.

The collection began in 1753, when Sir Hans Sloane, physician to Queen Anne and George II, bequeathed his personal collection of curiosities and antiquities to the nation. It then quickly grew, thanks to enthusiastic kleptomaniacs after the Napoleonic Wars -- most notoriously the seventh Earl of Elgin, who acquired the marbles from the Parthenon and Erechtheum during his term as British Ambassador in Constantinople in the days when Greece was part of the Turkish Empire.

The enormous building, with its classical Greek-style facade featuring figures representing the Progress of Civilization, was finished in 1847, the work of Sir Robert Smirke. Wherever you go, there are marvels, but certain objects and collections are more important, rarer, older, or downright unique, and because you may wish to include these in your wanderings, here follows a highly edited overview (in order of encounter) of the BM's greatest hits:

Close to the entrance, in Room 4, is the Rosetta Stone, found in 1799 and carved in 196 BC with a decree of Ptolemy V in Egyptian hieroglyphics, demotic, and Greek. It was this multilingual inscription that provided the French Egyptologist Jean-François Champollion with the key to deciphering hieroglyphics. Perhaps the Elgin Marbles ought not to be here, but since they are you can find them in Room 18 in the Parthenon Galleries.

Upstairs are some of the most popular galleries, especially beloved by children: Rooms 62-63, where the Egyptian mummies live. The Roxie Walker Galleries have a fascinating collection of relics from the Egyptian realm of the dead -- in addition to real corpses, wrapped mummies, and mummy cases, there's a menagerie of animal companions and curious items which were buried alongside them.

Proceeding clockwise, you'll come to Room 49, where the Mildenhall Treasure glitters in the refurbished Weston Gallery of Roman Britain. This haul of 4th-century Roman silver tableware was found beneath the sod of a Suffolk field in 1942. Next door, in Room 41, is the equally splendid Sutton Hoo Treasure, including brooches, swords and helmets, encrusted with jewels -- which was buried at sea with (it is thought) Redwald, one of the first English kings, in the 7th century and excavated from a Suffolk field in 1938-39. The area still holds ancient warrior graves, as excavations in 2001 revealed: some of the discoveries, such as a chieftain's shield, are on display at the museum.

In Room 50 lies Pete Marsh, so named by the archaeologists who unearthed the Lindow Man from a Cheshire peat marsh. He was ritually slain, probably as a human sacrifice, in the 1st century and lay perfectly pickled in his bog until 1984. In the upper level of the museum is the Money Gallery, which holds ancient coins and medals.

Also worth a look: The Korea Foundation Gallery (Room 67) delves into the art and archaeology of the country, including precious porcelain (much admired by today's artist potters), and colorful, intricately worked screens; and the Sainsbury African Galleries, which present a staggering 200,000 objects, including intricate pieces of old ivory, gold, and wooden masks and carvings. Make sure to join at least one of the free "Eyeopener" 50-minute tours by museum guides (details at the information desk) -- they do just what they say. COST: Free, suggested donation of £2. Tube: Tottenham Court Rd., Holborn, or Russell Sq.