Author of the book: Juan Mañe y Flaquer. Numbering of the engraving in the book: nº 37. Autographed. "This valley, [...] forms a kind of fork, whose branches are the valleys of Bolivar and Echevarria, that support their upper ends on the abutments of mounts Aoiz and Urco. The town of Marquina is at the angle formed by the meeting point of both rivers that flow down from these valleys"