Biscay (in Basque and officially Bizkaia and in Spanish Vizcaya) is a province of Spain located just south of the Bay of Biscay. The name also refers to a historical territory of the Basque Country, heir of the ancient Lordship of Biscay. Its capital city is Bilbao. It is one of the most prosperous and important provinces of Spain as a result of the massive industrialization in the last years of the 19th century and first half of the 20th century. Since the deep deindustrialization of the 1970s, the economy has come to rely more on the services sector.