Borghese Gallery, Rome

A small museum in a 17th-century villa in the Villa Borghese park, with one of the finest art collections in the world: Bernini's breathtaking marble sculptures, including Apollo and Daphne and The Rape of Proserpina, and paintings by Caravaggio, Raphael and Titian.

Visits are limited to two-hour slots and must be booked in advance, which keeps it uncrowded. Afterwards, walk or hire a bike in the park, and look out over the city from the Pincio terrace above the Piazza del Popolo.