Gallo-Roman enclosure of Le Mans

The Gallo-Roman enclosure of Le Mans, also referred to as the Roman enclosure of Le Mans, is located in the city once known as Vindinum or Vindunum. This city was the capital of the Gallic people, the Aulerci Cenomani. The construction of the enclosure began during the Late Roman Empire. While it was previously believed to date from the end of the 3rd century, recent studies suggest a construction date at the beginning of the 4th century.

The construction work was carried out according to an organized plan and at a considerable cost, which, according to Joseph Guilleux, was indicative of the affluence of the city and its territory. The enclosure retained its military function throughout the Middle Ages and was preserved due to the rise in ground level within the enclosures, which afforded it a supporting role. Following the Middle Ages, the construction of buildings in its immediate vicinity contributed to its longevity.

Source: Wikipedia