View of sunset over terracota rooftops and Douro River in the old town of Porto, Porto, Norte, Portugal, Europe

photography panoramic color image travel destinations travel outdoors sunset dusk no people portugal europe terracotta roof building architecture douro river city urban scene river water old town porto cloud sky rooftop sunshine sunlight dramatic sky travel destination tourist destination tourist destinations sunny sundown evening twilight skies rivers flowing water outdoor outside old towns town towns nobody no one no person cities urban buildings architectural