The Museu de Portimão is one of the most rewarding regional museums in southern Portugal, occupying the vast brick-and-tile former Feu Hermanos sardine cannery on the Arade river. The cannery operated until 1995, and the museum has preserved the original equipment in place: a complete industrial archaeology of the Algarve fishing economy across the twentieth century.
Beyond the cannery exhibit, the museum covers the area's broader history — Phoenician trade, Roman fish-salting sites, medieval fortifications, the modern town. The audio guide is good and free. The cafe in the courtyard, looking out over the river, is one of the better lunch spots in Portimão.
The museum is in central Portimão, a short bus ride or 25-minute walk from Praia da Rocha.