The name Périgueux comes from Petrocorii, a Latinization of Celtic words meaning "the four tribes" – the Gallic people that held the area before the Roman conquest. Périgueux was their capital city. In 200 BC, the Petrocorii came from the north and settled at Périgueux and established an encampment at La Boissière. After the Roman invasion, they left this post and established themselves on the plaine of L'Isle, and the town of Vesunna was created. This Roman city was eventually embellished with amenities such as temples, baths, amphitheatres, and a forum. At the end of the third century AD, the Roman city was surrounded by ramparts, and the town took the name of Civitas Petrocoriorum.