Grand Canyon

The Grand Canyon slices across the Colorado Plateau in the U.S. state of Arizona. Stepped cliffs display nearly two billion years of Earth history, from ancient Vishnu Schist at the river to younger Kaibab Limestone along the rim. The canyon averages 16 kilometers wide and more than 1,800 meters deep, with desert scrub near the rim and cottonwood oases along the river. Sunrise and sunset light paint the walls red, orange, and purple, helping hikers understand why the canyon is called one of the natural wonders of the world.

The Colorado River and its tributaries sculpted the canyon over millions of years through uplift, erosion, and weathering. Seasonal storms, snowmelt, and flash floods continue to chip away at the cliffs, while freeze-thaw cycles crack boulders that tumble toward the valley floor. Scientists study fossils, mineral deposits, and microfossils preserved in the rock layers to reconstruct ancient seas, deserts, and volcanic episodes. Rafting trips experience the canyon's geologic story firsthand, passing towering walls and rapids such as Granite and Lava Falls.

The canyon is also home to diverse wildlife. California condors soar above the rim after successful recovery programs, bighorn sheep climb steep ledges, and ringtail cats prowl at night. Along the river, willows and tamarisk provide shade for humpback chub fish and Southwestern willow flycatchers. Rangers and scientists monitor invasive species, manage controlled burns to restore ponderosa pine forests, and collaborate with tribal nations on habitat restoration projects.

People have lived in the Grand Canyon region for thousands of years. The Havasupai, Hualapai, Hopi, Navajo, Zuni, and other Indigenous nations maintain cultural ties to the land. Puebloan cliff dwellings, petroglyphs, and trails mark centuries of trade and ceremony. Today, tribal guides share stories with visitors, and a Tribal Park on the west rim operates the Skywalk, a glass bridge that extends over the canyon. National Park Service staff work with tribes to protect sacred sites and incorporate traditional ecological knowledge into resource management.

Visitors can explore the South Rim's paved paths, shuttle system, and visitor centers, or venture to the quieter North Rim, which sits about 300 meters higher and closes during winter snow. Popular trails such as Bright Angel and South Kaibab descend to Phantom Ranch, where hikers rest before climbing back up. Safety is critical: heat, dehydration, and sudden storms can catch travelers off guard, so rangers emphasize planning, water, and Leave No Trace practices. Night-sky programs highlight the park's designation as an International Dark Sky Park, inviting guests to view the Milky Way over the canyon walls.