Though most of this square just south of Piazza de Ferrari is made of 1930s office buildings, one end is bounded by the twin round towers of the reconstructed Porta Soprana ★★, a town gate built in 1155. The main draw, though, is the small house (rebuilt in the 18th c.), still standing a bit incongruously in a tidy little park below the gate, said to have belonged to Christopher Columbus’s father, who was a weaver and gatekeeper (whether young Christopher lived here is open to debate).