Porto, also known as Oporto in English, is the second largest city in Portugal and one of the major urban areas in the Iberian Peninsula. Its administrative limits include a population of 237,559 inhabitants. The urbanized area of Porto, which extends beyond the administrative limits of the city, has a population of 1.3 million, making it the second-largest urban area in Portugal.

Located along the Douro river estuary in northern Portugal, Porto is one of the oldest European centres, and registered as a World Heritage Site by UNESCO in 1996. Its settlement dates back many centuries, when it was an outpost of the Roman Empire. Its Latin name, Portus Cale, has been referred to as the origin for the name "Portugal," based on transliteration and oral evolution from Latin.

One of Portugal's internationally famous exports, port wine, is named after Porto, since the metropolitan area, and in particular the adegas of Vila Nova de Gaia, were responsible for the production and export of the fortified wine.