Nestor Basterretxea Arzadun was a Basque artist, born in Bermeo, Biscay, Basque Country. In the 1950s and 1960s, he spearheaded along with other artists such as Jorge Oteiza, Remigio Mendiburu, or Eduardo Chillida, an avant-garde artistic movement concerned with the crisis of Basque identity, and formally a special focus on large volumes and the concept of emptiness.