Francisco de Sá Carneiro Airport — Porto, Portugal

Named for the Portuguese prime minister killed in a 1980 plane crash, OPO serves Porto and the surrounding north of Portugal from its site at Pedras Rubras, a short metro ride from the historic riverside city. It ranks as Portugal's second-busiest airport after Lisbon, and a striking terminal expansion completed in 2007 gave it a light-filled, award-winning design that reshaped how travelers arrive in the region. TAP Air Portugal operates a secondary base there, while Ryanair and easyJet have built dense networks of low-cost routes across Europe, reflecting Porto's rise as a favorite short-break destination known for its port wine cellars across the river in Vila Nova de Gaia. The airport also functions as a practical entry point for travelers heading further into the Douro Valley wine region, a landscape of terraced vineyards that draws visitors well beyond the city itself.