Porto is a large Portuguese city on the Atlantic Ocean. There is the mouth of the river Douro. The double-deck Dom Luis I bridge was built in the 19th century and is one of the landmarks of the city. The steel structure was named in honor of King Luís I and has spanned the two banks of the river since 1886. The total length of the bridge is 385 meters and it was designed by Téophile Seyrig. The bridge leads from the center of Porto to the district of Vila Nova de Gaia, which is known for the cellars where the world famous wine was kept. Dom Luís I Bridge is the only double-deck bridge on the Douro River.