Torre dos Clérigos

Sticking out on Porto's skyline like a sore thumb – albeit a beautiful baroque one – this 76m-high tower was designed by Italian-born baroque master Nicolau Nasoni in the mid-1700s. Climb its 225-step spiral staircase for phenomenal views over Porto's tiled rooftops, spires and the curve of the Douro to the port-wine lodges in Gaia. It also harbours an exhibition that chronicles the history of the tower's architects and residents.