From the view on Las Ventanas (The Dolphin effigy), walk upstream Mascun Canyon 800 meters to the signed trail named "La Costera" (left) which lead to the abandonned hamlet of Otin. Hike up (north) La Costera 15 minutes to "la Cuidadela"(The Citadel) and the curious monolith called "La Cuca" on the right side of the trail. La Cuidadela is pierced by two natural opening on the top.