View of the terracotta rooftops of The Ribeira district overlooking the Douro River, UNESCO World Heritage Site, Porto, Norte, Portugal, Europe

photography horizontal color image travel destinations travel outdoors day incidental people portugal europe city urban scene porto douro river river water terracotta rooftop ribeira district building architecture cloud sky tree nature boat trees travel destination tourist destination tourist destinations skies rivers flowing water outdoor outside daytime cities urban buildings nautical vessel nautical vessels transport transportation architectural