A demanding stage through the Basque interior to Gernika, passing through the ancestral village of one of history's most famous figures. The route follows the rivers Lea and Artibai through Iruzubieta to Bolibar, the birthplace of Simon Bolivar's family. A museum in his ancestral house and a monument document the Liberator's Basque roots.

From Bolibar, a cobbled path climbs to the Monastery of Zenarruza (Ziortza), an 11th-century foundation still inhabited by a community of Cistercian monks who continue to welcome pilgrims. Beyond the monastery, the route passes through a robledal vetusto (ancient oak forest) shared between the municipalities of Mendata and Arratzu, described as one of the 'intact jewels of the Urdaibai Reserve.' The medieval bridge of Artzubi and the pentagonal Tower of Montalban are notable waypoints.

Gernika-Lumo is forever associated with the 1937 bombing, but the town's significance to Basque identity runs far deeper. The historic Oak Tree (Gernikako Arbola) and the Casa de Juntas represent centuries of Basque self-governance. The Parque de los Pueblos de Europa houses sculptures by Chillida and Henry Moore. The Monday market has run since the town's founding in 1366.