High atop Monte Mario, the Cavalieri Hilton's rooftop La Pergola restaurant offers a commanding view of the city below. Trompe-l'oeil ceilings and handsome wood paneling combine with low lighting to create an intimate atmosphere. Celebrated Wunder-chef Heinz Beck brings Rome its most polished example of Mediterranean alta cucina (haute cuisine); dishes are balanced and light, and presentation is striking. For a window table reserve a month in advance; otherwise, two weeks. Reservations essential. Jacket and tie.