Tooth of Time, Mountain summit in Colfax County, New Mexico, US.

Tooth of Time is a pinkish-gray dacite porphyry intrusion on Philmont Scout Ranch, five miles southwest of Cimarron, New Mexico. It rises about 2,500 feet (760 m) above the valley floor as a sheer vertical face that supports little plant life. The summit, at 2,714 m, sits at the east end of Tooth of Time Ridge, with Shaefer's Peak at the west end.

Traders on the Santa Fe Trail knew the Tooth of Time as a landmark marking the last seven-day push to Santa Fe. The igneous dacite porphyry intrusion formed in the Paleogene Period, roughly 22 to 40 million years ago, when magma cooled within older sedimentary rock that later eroded away.

This summit serves as the main symbol of Philmont Scout Ranch, where thousands of young scouts undertake backcountry journeys during summer months. The distinctive peak holds special meaning for visitors who return to the area year after year.

Two main trails lead to the summit, offering different approaches through the surrounding wilderness. Visitors should prepare for a challenging hike and bring plenty of water, as the exposed rock face offers little shade along the way.

The first technical climb of the main rock face happened in 1972 when three climbers successfully completed a roped ascent. This historic moment opened the door for rock climbing activity on the formation and attracted climbers from far away.