1911 Encyclopædia Britannica/Augusta Praetoria Salassorum
AUGUSTA PRAETORIA SALASSORUM (mod. Aosta, q.v.), an ancient town of Italy in the 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 3000 praetorians. 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 considerable military importance, which is vouched for by considerable remains of Roman buildings. The ancient town walls, enclosing a rectangle 793 by 624 yds., are still preserved almost in their entire extent. The walls are 21 ft. high. They are built of concrete faced with small blocks of stone, and at the bottom are nearly 9 ft. thick, and at the top 6 ft. 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 twenty towers altogether. They are roughly 32 ft. square, and project 14 ft. from the wall. The Torre del Pailleron on the south and the Torre del Leproso in the west are especially well preserved. 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 arrangement of the streets perpetuates the Roman plan, dividing the town into 16 blocks (insulae). The main road, 32 ft. wide, divides the city into two equal halves, running from east to west, an arrangement which makes it clear that the guarding of the road was the main raison d’être of the city. Some arcades of the amphitheatre (the diameters of which are 282 ft. and 239 ft.), and the south wall of the theatre are also preserved, the latter to a height of over 70 ft., and a market-place some 300 ft. 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 5 m. 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 3½ ft. in width. There are considerable remains of the ancient road from Eporedia (mod. Ivrea) to Augusta Praetoria, up the Valle d’ Aosta, which the modern railway follows, notably the Pont St Martin, with a single arch with a span of 116 ft. and a roadway 15 ft. wide, the cutting of Donnaz, and the Roman bridges of Châtillon (Pont St Vincent) and Aosta (Pont de Pierre), &c.
See C. Promis, Le antichità di Aosta (Turin, 1862); E. Bérard in Atti della Società di Archeologia di Torino, iii. 119 seq.; Notizie degli Scavi, passim; A. d’Andrade, Relazione dell’ Ufficio Regionale per la conservazione dei Monumenti del Piemonte e della Liguria (Turin, 1899), 46 seq.