San Sebastián, officially known by the bilingual name Donostia / San Sebastián, is a city and municipality located in the Basque Autonomous Community in Spain. Situated on the coast of the Bay of Biscay, it lies approximately 20 km from the France–Spain border. The city serves as the capital of the province of Gipuzkoa.
As of 2024, the city has a population of 188,487, while its metropolitan area was recorded at 436,500 in 2010. Residents refer to themselves as donostiarra in both Basque and Spanish. The municipality is also a constituent part of the Basque Eurocity Bayonne-San Sebastián.