This is the fourth of my translations of the French language descriptions on the listing.
Originally a Roman town, flanked by a castle from the Middle Ages, Briancon was encircled by a new enceinte in 1690, to protect it from attack. After a fire in 1692, it was fortified in accordance with a Vauban design from 1692 to 1700 and, after his death, until 1734. The forts were built between 1709 and 1734. The Asfeld bridge was built in 1729 - 1731. The Y Communication was constructed between 1724 and 1734. Later, Salettes fort received a Haxo casemate in 1847 and in 1892 a cable car linked the Trois Tetes fort to the urban enceinte. To compliment, eight Sere de Rivieres forts were realised between 1876 and 1900 and six Maginot Lines ouvrages added from 1936 to 1939, forming the second and third circles around the town.