Desert and semidesert natural landscape of 42,000 acres in the southeast of Navarra, in Arguedas, within the province of Navarra. With clay soils, chalk and sandstone, it has surprising formations where canyons, plateaus tabular structure and solitary mountains, called seamounts stand out. Most of it is protected, since it is a natural park. In 2000 the area was declared a Biosphere Reserve.