Health Department Headquarters, Basque, Spain

Almost half the 2,155,546 inhabitants the Basque Country live in Greater Bilbao, Bilbao's metropolitan area. Of the ten most populous cities, six form part Bilbao's conurbation (Bilbao, Barakaldo, Getxo, Portugalete, Santurce and Basauri).
At 28.2% the Basque population born outside this region, immigration is crucial to Basque demographics. Over the 20th century most this immigration came from other parts Spain, typically from Galicia or Castile-Leon. Over the last years, sizeable numbers this population have returned to their birthplaces whereas immigration to the Basque country currently originates abroad, chiefly from South America.