Ribeira Pier is a district located on the banks of Douro River in the historic center of Porto. The streets are narrow in this area and buildings are in bright pastel colors. There is an historic monumental fountain from the 1780s featuring the coat of arms of Portugal in Ribeira Square. The Dom Luís I Bridge, is a double-deck metal arch bridge that spans the river Douro between the cities of Porto and Vila Nova de Gaia. At its construction, its 172 metres span, was the longest of its type in the world.(wikipedia)