Footbridge Cave

Footbridge Cave is a small opening in the inner canyon near the Colorado River crossing at the bottom of the corridor trails, in the stretch of Grand Canyon where the Black and Silver footbridges span the river between the South Kaibab and Bright Angel trails. This is the deepest, oldest part of the canyon exposed to hikers — the dark, hard walls here are Vishnu Schist and Zoroaster Granite, some of the oldest exposed rock in North America, cut through by the river over the last several million years rather than the softer, cave-riddled Redwall Limestone found higher up in the canyon's walls.

What to know

• Reached only by descending one of the corridor trails (South Kaibab or Bright Angel) to the river, a multi-thousand-foot descent with no shade or water for most of the way down.
• Sits in the inner gorge near Phantom Ranch and the Bright Angel Campground, not an above-rim roadside stop.
• Not a developed or signed visitor attraction — treat it as a minor feature of the inner gorge landscape rather than a hike destination in itself.