Foz de Arbaiun Nature · Romanzado/Erromantzatua, Sangüesa, Navarra A canyon about 6 km long and nearly 400 meters deep, carved by the Salazar river into the limestone rock of the Sierra de Leyre, between the municipal areas of Romanzado and Lumbier. Declared a Reserva Natural (Nature Reserve) in 1987, designated a Special Area of Conservation (ZEC) in 2004 and a Special Protection Area for Birds (ZEPA) in 2013, it holds the largest colony of griffon vultures in Navarre, along with golden eagles, Egyptian vultures, and bearded vultures. 1987 Photo: Colsandsol (CC BY-SA 4.0) What to see and do in Romanzado/Erromantzatua