Castillonuevo/Gazteluberri Village · Castillonuevo/Gazteluberri, Sangüesa, Navarra A late medieval settlement, probably from the late 12th century, which arose when residents of Elesa moved to settle next to a defensive fortress on the eastern border of Navarre. With 14 inhabitants in 2025, it is the least populous municipality in Navarre; it only achieved administrative independence from Navascués in 1859. s. XII Photo: Jialxv (CC0) What to see and do in Castillonuevo/Gazteluberri