The Fish Salting Factory of Cacilhas was discovered in 1981 during sanitation works. The industrial complex, evidence of the Roman presence in the municipality of Almada, was centered on producing fish preparations. It consisted of, at least, fifteen tanks or

cetariae organized around a central courtyard covered by mortar and gravel that served as a work area and provided access inside the reservoirs.

The factory operated in the open air, favoring the free circulation of air, with a ceramic hanging roof that protected the tanks. The exact period of operation is unknown, but the factory is estimated to have been built in the first century CE and remained active until the fourth or fifth centuries.

The Cacilhas factory was part of an extensive production network that included adjacent nuclei in Rua Carvalho Freirinha and also Porto Brandão (Caparica). Although smaller than the industrial dynamics on the north bank, it contributed to its supply, production and subsequent shipment. Along with the evident abundance of fish in the river, the supply of fish, salt, spices and transport

amphorae was essential for the Cacilhas complex to maintain its rhythm and production, in particular, in combination with the salt and

amphorae producing complexes, widely distributed throughout the Tagus estuary.

The situation after abandonment remains undefined. Rubble inside the

cetariae and the identification of a fireplace, food remains, and painted ceramics of Muslim inspiration reinforce the idea of permanence during the thirteenth century, extending to the Contemporary Period.

Currently the nucleus integrates the urban landscape of Cacilhas, protected by a glass structure at sidewalk level. Visitors can access multimedia resources that facilitate the interpretation of the archaeological site.