The ancient thousand-year abbey of the Sacra di San Michele, founded in the years between 983 and 987, is located within the municipality at the top of Mount Pirchiriano.

The urban center of Sant'Ambrogio is located in the lower Valle di Susa, on the orographic right of the Dora Riparia and at the foot of Mount Pirchiriano.

Noteworthy are the Palazzo Abbaziale di Sant'Ambrogio, of medieval origin (1176) and the city walls with a quadrangular structure, dating back to the 13th century.

Among the more recent buildings are the Town Hall (1871) located in Piazza XXV Aprile, the industrial complex of Maglificio Fratelli Bosio (1871) and the Antiche Mura Theater (19th century).

There are numerous religious architectures present in the municipal area: among them, the main one is the millenary abbey of the Sacra di San Michele, built in the period between 983 and 987.