Cantera, literally meaning "quarry" in Spanish, is a term used in Spain to refer to youth academies and farm teams organized by sports clubs. It is also used to refer to the geographical area that clubs recruit players from. The term is widely used in football but is also applied to other sports, such as basketball. This article, however, is about the football canteras. Notable canteras include those of Athletic Bilbao, Real Sociedad, Real Madrid, Barcelona, Atlético Madrid, Espanyol, Sporting de Gijón, Celta de Vigo and Valencia. Basque canteras Athletic Bilbao Since 1912, Athletic Bilbao have employed a "cantera policy", which has come to be defined in an official (although not legally binding) signing policy whereby they will only recruit players with some link to the Basque Country. One of the main beneficiaries of the policy has been the Spain national team. Athletic has provided numerous players for it, second only to Real Madrid. During the early 1920s, the Basque Country was a breeding ground of great Spanish players. It was the first area where the sport really became popular, and the influx of immigrants from all over Spain was also a factor in the region producing dozens of quality players. In 1920, Spain made their international debut and entered a team in the Olympic Games. Of the 21 players in the squad, 14 were Basques, among them Pichichi, José María Belauste, Domingo Acedo and Félix Sesúmaga. Throughout their history, Athletic Bilbao have continued to produce many notable players while adhering to their policy. Among them were Telmo Zarra, the then all-time top La Liga goalscorer; José Ángel Iribar, 614 official matches with Athletic and a member of the Spain team when they won the European Championship in 1964; and Andoni Zubizarreta, who made a record 622 La Liga appearances and is also the second most capped Spanish international player. Other notable graduates of the Athletic cantera include Bata, Agustín Gaínza, José Luis Panizo, Andoni Goikoetxea, Julio Salinas, Julen Guerrero, Rafael Alkorta, Andoni Iraola, Fernando Llorente and Kepa Arrizabalaga. Their youth teams continue to be among the most productive in Spain. Real Sociedad Athletic were not the only club to have a cantera policy — fellow Basque club Real Sociedad operated a similar policy until 1989. Neither were Athletic the only Basque club that provided players for the 1920 Olympics squad. Real Sociedad, Real Unión and Arenas Club de Getxo