Located on the road linking Milan to Arles, Briançon - then Brigantio - has been an essential crossing point since Roman times. The town retreated to the fortified peak overlooking the Durance valley during the Migration Period (5th to 9th centuries). Dauphinoise from the 11th century then capital of the Escartons (a federation of 52 communities) from 1343, Briançon developed around trade and fairs until the Italian and religious wars of the 15th and 16th centuries. Destroyed by two fires in 1624 and 1692, it was rebuilt inside an enclosure designed by Vauban while retaining its medieval plot. The establishment of the border at Montgenèvre following the Treaty of Utrecht in 1713 reinforced the military character of Briançon by providing it with high forts built after Vauban's death.