The Basque Country, also called the Basque Autonomous Community, is an autonomous community in northern Spain. It includes the Basque provinces of Álava, Biscay, and Gipuzkoa. It also surrounds an enclave called Treviño, which belongs to the neighboring autonomous community of Castile and León.

The Treviño Enclave in northern Spain is part of the territory of the province of Burgos, but is completely surrounded by the territory of the Basque Country province of Álava. Thus, it is an enclave of the Basque Country and an exclave of Castile and León. It consists of two municipalities—Condado de Treviño and La Puebla de Arganzón—and is part of the Judicial district of Miranda de Ebro in the province of Burgos.