Galerias Romanas da Rua da Prata

The Roman Galleries of Rua da Prata lie hidden beneath Lisbon’s Baixa, between Rua da Prata and Rua da Conceição, as one of the most discreet traces of ancient Olisipo. Dating from the 1st century AD, they are now interpreted as a cryptoporticus: a vaulted stone structure created to form a stable platform on which large buildings could stand. Their presence was identified in 1771, during the Pombaline reconstruction that followed the 1755 earthquake. Flooded by underground water, the galleries maintain a physical relationship with the damp ground of the riverside city. Inside, corridors, vaults and masonry walls reveal the technical scale of Roman construction. Beneath the regular grid of modern Lisbon, this space preserves an ancient, silent and essential layer of the city.