Porto lies in the north of Portugal on the Atlantic Ocean. The steel Dom Luís I is the bridge which is one of the landmarks of the city. This double-decked crossing on the river Douro was opened for the inhabitants of Porto in 1886. The bridge was designed by Teófilo Seyrig, a disciple of Gustav Eiffel. It is named after Luís I – Portuguese king in the years 1861-1889. At the time of its construction it was the world’s longest bridge of this type. The structure with a distinctive arch that spans Porto and Vila Nova de Gaia is beautifully illuminated at night.