Porto, PAWR too (pop. 302,467),is Portugal's second largest city. Only Lisbon is larger. The municipality of Porto has a population of 263,131. A municipality may include rural areas as well as the urban center. Porto is also called Oporto. It is one of the country's chief seaports and serves as the commercial and industrial center of northern Portugal. It lies on the Douro River, 3 miles (5 kilometers) from the Atlantic Ocean. Porto is known for its role in processing and exporting Portugal's excellent port wines. The city also has food-processing plants, sugar refineries, textile mills, and other industries. Principal landmarks in Porto include the cathedral, which dates from the 1100's, and the bishop's palace, built during the 1700's. The Arrabida Bridge, one of three bridges across the Douro at Porto, is one of the longest concrete arch bridges in Europe. The University of Porto was founded in 1911.