Crater Ice Cave / Big Pryor Mountain

Revised 9/29/12
Download printable Crater Ice Cave / Big Pryor Mountain hiking guide.

Previous versions of this guide refer to scrambling over many logs fallen across the trail and pushing through brush. In late September a Custer National Forest crew cleared the logs and brush. The trail is now clear to the top.

This is a short and steep trail from Tie Flat (near the north end of Crooked Creek Road) to Crater Ice Cave and the top of Big Pryor Mountain. In a distance of 1.7 miles (one way) it climbs 1,600 feet up the northeast corner of Big Pryor Mountain. Much of the climb is through a thick forest of Douglas fir. The climb is cool, quiet and secluded. Look for abundant squirrels and occasional dusky grouse. Striped Coralroot, an orchid, may be seen blooming near the trail – perhaps in June. Black bear have also been seen on this trail. Viewpoints are scarce on the lower trail, but peeks through the trees are increasingly frequent on the higher switchbacks. The massive view from the highest point in the Pryors (8,786 feet elevation) includes East Pryor Mountain, the Bighorn Mountains, the Beartooths, the plains of Montana to the north, and much of Wyoming including the Wind River Mountains to the south. Wildflowers can be profuse on the subalpine plateau in late June or early July depending on the season.

Big Pryor Mountain from the East  (Photo by Dick Walton) Big Pryor Mountain from the East (Photo by Dick Walton)
Crater Ice Cave / Big Pryor Mountain Trail Map.  Trailhead on Tie Flat Rd - Yellow Arrow.  0.4 mile Trail Sign - Yellow Diamond.  Crater Ice Cave - Purple Diamond.  Top of Big Pryor Mountain - Purple Triangle.  (<i>Red GPS Track by Jim Reid</i>) Click to Expand - Crater Ice Cave Trail Map

There is no sign marking the trailhead on Tie Flat Road. There is a trail sign at an important location 0.4 miles up the trail, but it is not well placed to indicate the continuation of the trail. The directions below should get you to the trailhead and past the 0.4 mile point. Once found it is a pretty good trail and easy to follow.

This is the only trail in the Pryors designated for hiking by Custer National Forest (CNF). The Pryors Coalition believes CNF needs to improve the trail signing, and publish a hiking guide to this, and other non-motorized routes
in the Pryors.

Getting to the Trailhead:

Tie Flat Rd and sign at junction with Pryor Mountain Rd (#2308). Tie Flat Rd and sign at junction with Pryor Mountain Rd (#2308).
From Bridger MT follow the instructions and map for Pryor Mountain Road, or use the Pryor Mountain Map set.
At 29.7 miles from Highway 310 on Pryor Mountain Road turn right (south) on the two track Tie Flat Rd. #2104. (This is 7.7 miles from the cattle guard where Pryor Mountain Rd. (#2308) enters Custer NF, and 0.6 miles southwest on #2308 from the Crooked Creek Rd. junction.) Follow #2104 for 0.1 mile to a junction with a two track trail to the right (southwest). Route #2104 continues straight ahead without a sign.

Park here. This is the unmarked trailhead. The two-track trail to the right is the trail and is signed “No Motor Vehicles” about 300 ft from the trailhead.

The Trail:

Walk southwest up the two-track trail for 0.4 miles. At first it is in open grassland and sagebrush, but soon enters the trees. After 0.4 miles, and 300 ft elevation gain, the track arrives at a flat opening in the trees. The two old logging tracks to the right (north), signed #2002A and #2002A1, are motor-legal, but little used.

Trail beginning from Tie Flat route #2104.  Deer on trail. Trail beginning from Tie Flat route #2104. Deer on trail.
0.4 mile clearing, trail sign and trail (arrow). 0.4 mile clearing, trail sign and trail (arrow).
There is a new “Crater Ice Cave Trail” sign across the clearing to the left. The track to the left is not motor-legal. Follow the left (south) track about 50 feet beyond the sign. At that point a narrow footpath leaves the main track and enters the gulley to the right. This is the trail. See photo.

At first the trail is fairly primitive, formed only by the impact of previous hikers – like a game trail. The trail goes about 40 or 50 feet up the bottom of the gulley, then climbs out the right (north) side. It then continues west paralleling the gulley on its north side for a couple hundred feet through open grass and low brush (snowberry and Oregon grape) before entering thick timber.

Primitive trail paralleling gully. Primitive trail paralleling gully.
Saw cut logs beside primitive trail where it enters trees. Saw cut logs beside primitive trail where it enters trees.

As you enter the timber you will see several saw cut logs beside the trail. The trail then makes a right angle turn to the right (north).



From this right turn on the trail follows a quite obvious, old, constructed trail bed about 1 ¼ mile, 1,200 ft elevation, and 14 switchbacks to the top. It is fairly easy walking, but steeply uphill. Just below the top the trail forks. The left fork curves into the trees to Crater Ice cave. The right fork continues to the top of Big Pryor Mountain. There is a large marker post at the top, an “Unauthorized Trail” sign indicating the end of 4WD route #2088 from the south, and another “Crater Ice Cave Trail” sign.

Crater Ice Cave Crater Ice Cave
Inside Crater Ice Cave, HDR photo by Craig Christopherson Inside Crater Ice Cave, HDR photo by Craig Christopherson


Extending your hike:

There is a faint two track route heading NW from the top of Big Pryor Mountain. It is not legal for motorized use and thus an inviting hiking route. There is a sign indicating it is an “Unauthorized Trail” for motor vehicles. After 2.2 miles this track reaches another motorized route #2095A.

A second alternative is to follow the ridgeline south along, and parallel to motorized route #2088. It is a gentle, slightly down hill walk to Red Pryor Mountain which is a “bump” about 100 ft elevation above the ridge. If you go all the way to Red Pryor Mountain this adds an additional 6 miles (round trip), and 500 ft elevation gain (mostly on the return) to the hike.