[1][2] In Roman times, the richness of fish and salt in the estuary of the Sado River led to the creation of salted-fish industries centred on the towns of Cetóbriga (now Setúbal) and Tróia.

It was only in 1987 that the first archaeological excavation was carried out, by the Museum of Archaeology and Ethnology of Setúbal District (Museu de Arqueologia e Etnografia do Distrito de Setúbal (MAEDS)), led by Carlos Tavares da Silva.

These salting tanks were lined by an opus signinum, as a form of waterproofing, composed of gravel mortar, hydraulic lime and sand.

Also during the first phase of occupation, towards the end of the 1st century AD, changes were made in the fish-processing facilities with the addition of two new tanks.

At this time construction work consisted mainly of repairs to the existing structures so fish processing could once again be carried out.