Opened in 1913, it is Spain's oldest built stadium (the oldest playing field being El Molinón), a distinction that together with its religious heritage has granted it the nickname, La Catedral (The Cathedral). San Mamés can seat almost forty thousand people and is renowned for the unique and boisterous atmosphere its crowds of devoted and loyal fans create on match-days.
The current stadium was almost entirely rebuilt to host matches in the 1982 FIFA World Cup. In March 2006, a project was approved to replace the stadium with a new and larger version, thereby increasing the stadium capacity to 53,000. The New San Mamés Stadium will be built on the former site of the Bilbao International Trade Fair, adjacent to the current stadium. Construction is scheduled to begin in April 2010, and when it is three quarters completed, Athletic Club will move into their new home and the original San Mamés will be demolished.