Though it's a hike from the center, this state-of-the-art museum is a good place to set the tone and context for your exploration of Arles. You can learn all about the city in its Roman heyday, from the development of its monuments to details of daily life. The bold, modern triangular structure (designed by Henri Ciriani) lies on the site of an enormous Roman cirque (chariot-racing stadium), and the permanent collection includes jewelry, mosaics, town plans, and carved 4th-century sarcophagi. A wing of the museum features a rare intact barge dating from AD 50 and a fascinating display illustrating how the boat was meticulously dredged from the nearby Rhône. The quantity of these treasures gives an idea of the extent of Arles's importance. Seven superb floor mosaics can be viewed from an elevated platform, and you exit via a hall packed tight with magnificently detailed paleo-Christian sarcophagi. As you leave you will see the belt of St-Césaire, the last bishop of Arles, who died in AD 542 when the countryside was overwhelmed by the Franks and the Roman era met its end. Ask for an English-language guidebook.