Canyon de Chelly National Monument ( ) was established on April 1, 1931, as a unit of the National Park Service. Located in northeastern Arizona, it is within the boundaries of the Navajo Nation and lies in the Four Corners region. Reflecting one of the longest continuously inhabited landscapes of North America, it preserves ruins of the indigenous tribes that lived in the area, from the Ancestral Puebloans (also known as the Anasazi) to the Navajo. The monument covers and encompasses the floors and rims of the three major canyons: de Chelly, del Muerto, and Monument. These canyons were cut by streams with headwaters in the Chuska Mountains just to the east of the monument. None of the land is federally owned. Canyon de Chelly is one of the most visited national monuments in the United States. Etymology The name Chelly (or Chelley) is a Spanish borrowing of the Navajo word , which means "canyon" (literally "inside the rock" < tsé "rock" + -yiʼ "inside of, within"). The Navajo pronunciation is . The Spanish pronunciation of de Chelly was adapted into English, apparently modeled on a French-like spelling pronunciation, and is now . History Canyon de Chelly long served as a home for Navajo people before it was invaded by forces led by future New Mexico governor Lt. Antonio Narbona in 1805. In 1863, Col. Kit Carson sent troops through the canyon, killing 23 Navajo, seizing 200 sheep, and destroying hogans, as well as peach orchards and other crops. The resulting demoralization led to the surrender of the Navajos and their removal to Bosque Redondo, New Mexico. Description Canyon de Chelly is entirely owned by the Navajo Tribal Trust of the Navajo Nation. It is the only National Park Service unit that is owned and cooperatively managed in this manner. About 40 Navajo families live in the park. Access to the canyon floor is restricted, and visitors are allowed to travel in the canyons only when accompanied by a park ranger or an authorized Navajo guide. The only exception to this rule is the White House Ruin Trail. The park's distinctive geologic feature, Spider Rock, is a sandstone spire that rises from the canyon floor at the junction of Canyon de Chelly and Monument Canyon. Spider Rock can be seen from South Rim Drive. It has served as the scene of a number of television commercials. According to traditional Navajo