This beautiful shop carries dozens of canned seafood brands (representing hundreds of varieties) from Portugal, all labelled with details on the history of the maker and the product. You'll find not only excellent sardines, tuna and mackerel but also sea bream, bacalhau (salted cod), octopus and sangacho de atum (tuna blood). The last is good on a bed of greens with a citrus dressing.
Some of the common varieties of canned fish may sell for lower prices at other stores. That said, this shop is like a mini-gallery of Portuguese canned seafood and the service is immaculate.