AUGUSTA PRAETORIA SALASSORUM (mod. Aosta, q.v.), ancient town of Italy, district of the Salassi, founded by Augustus about 24 B.C. on the site of the camp of Varro Murena, who subdued this tribe in 25 B.C., and settled with 3,00o praeto rians. Pliny calls it the last town of Italy on the north-west, and its position at the confluence of two rivers, at the end of the Great and Little St. Bernard, gave it much military importance, which is vouched for by considerable remains of Roman buildings. The ancient town walls, enclosing a rectangle 793 by 624yd., are 2I ft. high, concrete faced with small blocks. There are towers at the angles of the enceinte, and others at intervals, and two at each of the four gates, making a total of 20 towers altogether. They are roughly 32ft. square, and project 14ft. from the wall. The east and south gates exist (the latter, a double gate with three arches flanked by two towers, is the Porta Praetoria, and is especially fine), while the rectangular Roman street scheme divides the town into 16 blocks (insulae). The main east to west road, 32ft. wide, divides the city into two equal halves, showing that the city guard ed the road. Some arcades of the amphitheatre (diameters 282ft. and 239ft.) and the south wall of the theatre are also preserved, the latter to a height of over 7oft., and a market-place some 3oof t. square, surrounded by storehouses on three sides with a temple in the centre, and two on the open (south) side, and the thermae, have been discovered. Outside the town is a handsome triumphal arch in honour of Augustus. About 5m. to the west is a single arched Roman bridge, the Pondel, which has a closed passage, lighted by windows for foot passengers in winter, and above it an open footpath, both being about 31ft. in width. There are con siderable remains of the ancient road from Eporedia (mod. Ivrea) to Augusta Praetoria, up the Valle d'Aosta, which the modern railway follows.