Porto's riverside district opens out on to the Douro here, looking across to the wine lodges of Gaia and the curving double-decker ironwork of the Dom Luis I bridge. To the east, the lanes of the Ribeira neighborhood run behind the row of narrow-fronted medieval townhouses. To the west are grey stone aches of grander buildings constructed during an 18th-century remodeling. Everywhere, the facades are enlivened with yellow, red and white paintwork or blue azulejo tiles. The northern side is filled with a three-story-high fountain built in the 1780s. Today, the square is filled with cafe terraces and is a hub of Porto's tourism, but it's not hard to imagine noisy fish trading and bustling quayside commerce that for centuries took place here.