As you cruise through the Douro River Valley, sail into the history of fine Portuguese wine. Surrounded by terraced hills, spot some of the area’s quintas, or wine estates, clinging to the slopes. Experience the town of Porto, where you can roam the port warehouses and take in the town’s rich cultural heritage. Visit quaint Régua, Barca d’Alva, and Favaios, home to one of the last traditional bakeries in the Douro Valley. Explore Salamanca, Spain, a UNESCO Site and one of Iberia’s oldest university towns.