The Maison au Dauphin (Dolphin House) of the archaeological site of La Villasse in Vaison-la-Romaine is the largest of its excavated dwellings. This rural dwelling with agricultural outbuildings built between 40 and 30 BC was transformed into a large city residence of 8,858 sq. ft (2,700 m²) over two centuries. From the entrance, visitors can spot the atrium and its basin, the impluvium, which still includes the four columns that supported the center-opened roof. This opening, known as the compluvium, allowed the collecting of rainwater.