Set in the 18th-century baroque Palacio de Allende-Salazar, this is the most comprehensive museum of Basque ethnography and political history outside Bilbao. Twelve rooms cover prehistory, the medieval House of Biscay, the Carlist wars, the fueros, Basque emigration to the Americas, and modern Basque nationalism.
Less visited than its neighbours but rewarding if you have already done the Casa de Juntas and want the broader context. English captions throughout.