Lusitanian raids and rebellions during Roman occupation required the construction of a wall around the settlement. During Augustus' reign, the Romans also built a great theatre; the Cassian Baths (underneath ''Rua da Prata''); temples to Jupiter, Diana, Cybele, Tethys and Idea Phrygiae (an uncommon cult from Asia Minor), in addition to temples to the Emperor; a large necropolis under ''Praça da Figueira''; a large forum and other buildings such as insulae (multi-storied apartment buildings) in the area between Castle Hill and the historic city core. Many of these ruins were first unearthed during the mid-18th century (when the recent discovery of Pompeii made Roman archaeology fashionable among Europe's upper classes).