The town that gave the country (and port wine) its very name, Porto is Portugal’s second-largest metropolis after Lisbon. Sometimes called Oporto, it’s an age-old city that has one foot firmly in the industrial present. The old town, centered at Ribeira, was built on the hills overlooking the Douro River, and today is a UNESCO World Heritage Site. The 14th-century São Francisco church is a main attraction, as are the local port wine cellars, mostly located across the river at Vila Nova de Gaia.