The Basque derby is the name of the football local derby between Real Sociedad and Athletic Bilbao. It embodies the inter-city rivalry between Bilbao and Donostia-San Sebastián, respectively the capitals of the neighbouring provinces of Biscay (Bizkaia) and Gipuzkoa in the Basque Country region of Spain. It is also occasionally referred to as the AP-8 derby, referring to the name of the highway which connects the cities.
Rival supporters socialising together pre-match in San Sebastián, October 2011