Yucca House National Monument, the ruins of prehistoric Native American pueblos, located 15 miles (24 km) south of the town of Cortez in the southwestern corner of Colorado, U.S., near Mesa Verde National Park. Occupying about 10 acres (4 hectares)—34 acres (14 hectares) including a privately owned access road—the site was discovered in 1877 by William H. Holmes, a researcher for the U.S. Geological Survey. It was declared a national monument in 1919, though it has remained unexcavated and largely unexplored; however, several hundred artifacts have been recovered from the surface. The ruins consist of one mound rising as high as 20 feet (6 metres) and surrounded by smaller mounds. Limestone from the vicinity was used by the inhabitants to build their settlement. The monument, long closed to the public, is now accessible via the private road.