Advanced Caving on the Abaro-Gentilzubi Traverse, Vizcaya

Context The Abaro-Gentilzubi traverse is an advanced underground route located in the Arratia karst valley, in Vizcaya. This cave system spans several hours of continuous exploration, combining dry and wet zones with natural formations and local wildlife. The journey begins at the Abaro shaft, guided by the sound of a dry riverbed, and concludes at the Jentilzubi entrance, creating a rare linear passage in the region. ">The Experience After equipping at the Abaro entrance, participants descend via technical rappels and navigate narrow galleries, overcoming handholds, obstacles, and tight squeezes. The humid atmosphere carries strong natural scents, including those from local crabs inhabiting certain sections. The cool air and echoing water sounds accompany the exploration, which lasts between 3 and 4 hours underground. ">For Whom This activity is designed for experienced cavers with solid physical fitness, aged 8 and older, who are confident in rappelling techniques and comfortable in confined, damp spaces. It is not suitable for beginners, individuals with vertigo, or those with a fear of enclosed areas. ">Local Context The Arratia valley, near Portugalete, is a protected natural area with a long-standing caving tradition. The local community values the preservation of the karst landscape and its subterranean biodiversity, including native crabs that contribute a distinctive scent to the wet passages.