San Sebastián, officially known by the bilingual name Donostia / San Sebastián, is a city and municipality located in the Basque Autonomous Community in Spain. It serves as the capital city of the province of Gipuzkoa and is situated on the coast of the Bay of Biscay, approximately 20 km from the France–Spain border.
The city has a population of 188,487 as of 2024, with its metropolitan area reaching 436,500 in 2010. Residents refer to themselves as donostiarra in both Basque and Spanish. Additionally, the city is a member of the Basque Eurocity Bayonne-San Sebastián.