“A flat, easy trail with views of some interesting and unique volcanic features.”
— QuinTCM TCM
River/Creek · Views
The trailhead is found at the end of Pinnacles Road and is well-marked and maintained. Follow the trail to where it ends near a large stone structure that likely once held a sign welcoming guests to Crater Lake NP. Beyond this structure, the trail continues for a very short distance then joins a dirt road. There isn't much to see beyond the stone structure so it is best to turn around there.
Along the trail, there are several short side trails that lead to the edge of the ravine that Wheeler Creek (and a little further along, Sand Creek) flows through. These trails offer great opportunities to view the pinnacles for which the trail is named. The pinnacles are large fossil fumaroles.
A very long time ago, super-heated pumice and other volcanic material flowed from Mount Mazama and covered the creek running through the canyon. As these materials cooled, very hot steam and gases moved up through this material and formed vents by cementing the surrounding rock together. Over time, the softer ground surrounding these hardened vents eroded away, leaving the fumaroles exposed.