The base of Collier Cone, at Opie Dildock Pass, can be reached by way of the Pacific Crest Trail. There are 3 different approaches, all of which are about the same distance. Options are available to turn this into a very nice loop for a long day hike, or an overnight backpacking trip with amazing campsites along the way. All of the trailheads can be found along HWY 242 (McKenzie Pass Highway).
Obsidian and Scott Trails can be accessed from the Frog Camp parking area. (NOTE: Frog Camp is not really a campground, just a loop with many parking spots) About 4 miles west of McKenzie Pass there is a well-marked sign for the Obsidian Trailhead (3528). From here you have an option to take either trail.
From the Obsidian Trail (3528) continue east to the Glacier Creek Trail (4336), and then north onto the PCT. It is just a little over 6 miles to the base of Collier Cone.
To join up with the Scott Trail (3531) take a quick left about 50 yards up the Obsidian Trail and follow that trail for about a half mile and then a right onto the Scott Trail (3531). Follow this trail east past Four-In-One Cone and take a right onto PCT and follow it south until you reach the base of Collier Cone. This route is about 7 miles to the base.
Another option is joining up with the PCT from the Lava Camp Lake area less than a mile east of McKenzie Pass. This route is nearly 7 miles as well, but there is not really a good loop option.
NOTE: If you plan on hiking the Obsidian Trail (3528) make sure you have a Limited Entry Permit – See Red Tape
From the base of Collier Cone follow the obvious trail that leads up to Collier Glacier viewpoint a small saddle on the south rim. From here follow the rim about halfway across to the true summit. You can make a small loop by descending down the north rim. This makes for a quick descent as you can scree ski all the way back down.
Gaiters are highly recommended.
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