Editing Athletic Bilbao (section)

=== Real Sociedad ===
{{main|Basque derby}}
Athletic Club's main historical rival is [[Real Sociedad]], a neighboring club against which it plays the classic Basque derby.<ref>{{Cite web |last=Gabilondo |first=Aritz |date=2021-04-03 |title=El sueño de la Copa era Real |url=https://as.com/futbol/2021/04/03/copa_del_rey/1617467299_513055.html |access-date=2024-03-19 |website=Diario AS |language=es}}</ref> Both teams have maintained a great rivalry since their beginnings, and although Athletic had a notably superior trajectory for many decades, since the 1980s the differences between both clubs have equalized significantly and, at the same time, the rivalry has increased.<ref>{{Cite web |title=Reportaje: Derbi vasco - Marca.com |url=http://archivo.marca.com/reportajes/07/01/26/derbi_vasco/historia.html |access-date=2024-03-19 |website=archivo.marca.com}}</ref><ref>{{Cite web |last=Sánchez |first=Pablo |date=2021-06-13 |title=Se cumplen 11 años del retorno de la Real Sociedad a la élite |url=https://www.eldesmarque.com/futbol/real-sociedad/20210613/crecimiento-exponencial-se-cumplen-11-anos-del-retorno-a-la-elite_151297419.html |access-date=2024-03-19 |website=ElDesmarque |language=es}}</ref>