Keyhole Arch Rock Climbing

Keyhole Arch is the prominent arch rising to the east above the Tongue River Canyon parking area. The arch is composed of limestone and dolostone of the Madison formation and rock quality is generally poor, but sections of fair rock quality are found on the summit block. There are no bolts or fixed anchors. Extreme caution should be exercised while climbing and placing gear. The arch can be climbed in two pitches. The first pitch gains a brushy and grassy ledge at the base of the arch (where one can walk beneath the arch). From this ledge, the summit may be gained via numerous possible trad lines. Descent is accomplished by tandem rappeling - half of the rope is tossed over each side of the arch. While small bushes and blocks could be slung, this method is cleanest as no slings or gear are abandoned on the summit.