Bandelier National Monument's 33,000 acres lay on the slopes of the Jemez Mountains. With elevations from just over 10,000 feet at Cerro Grande to just over 5,000 feet at the Rio Grande, the landscape encompasses sloped mesas cut by steep-walled canyons. Formed by massive volcanic eruptions over 1 million years ago, this place is home to a diversity of plant and animal life.