Vila Nova de Gaia, often referred to simply as Gaia, is a city and municipality located in the Norte Region of Portugal. It is situated within the Porto District, specifically positioned south of the city of Porto on the opposite side of the Douro River.
The municipality covers an area of 168.46 square kilometres and has a population of 303,824 as of 2021. This population figure makes it the most populous municipality in the Norte Region and the third most populous in Portugal, following Lisbon and Sintra. Gaia is one of the 17 municipalities that comprise the Porto metropolitan area.