Marker Lake
Drainage: Rock Creek
Approaches: West Fork Rock Creek Trailhead — 9 mi, 6.5 on trail with 2.5 mi off-trail; 3,007 ft up · From Ship Lake — about 0.5 mi southwest and 340 ft up
Elevation: 10,936 feet
Fish: Yellowstone cutthroat (FWP)
Coordinates: 45.11396, -109.60361
Bugs: Minimal on our visit
Getting there
West Fork Rock Creek Trailhead. Drive past the campgrounds along the gravel access road to the main parking area.
FWP puts Marker at nine miles with two and a half of them off trail and 3,007 feet of climbing. That is the hardest approach of any lake in this basin. We did it as part of a four day trip out of the same trailhead, camping at about 9,400 feet and working the upper basin from there.
The hike
Marker was the last lake of the third day and the highest, about half a mile southwest of Ship and 340 feet above it.
At 10,936 feet it sits well above everything else in the cluster. Getting there means climbing a lot of vertical over a short distance on open rock, and there is no trail on any of it. The compressed grade is what makes this one harder than the rest of the basin rather than the distance.
Marker is 13.7 acres. FWP lists Yellowstone cutthroat, and the fishing was excellent. We caught hard fighting trout up to twenty inches, which is not something you expect at this elevation.
We were told this is the highest fishable lake in Montana. Whether or not that holds, it is the highest water anyone is likely to fish in this drainage.
Tips & safety
The rock shelter: there is a giant boulder near the lake outlet, and we built a rock shelter against it during our visit. Have a look and see if it is still standing.
Wind: this basin gets hammered. At nearly 11,000 feet with nothing anywhere near it, the exposure here is worse than anywhere else on the bench, which is why the shelter got built in the first place.
Fishing: Yellowstone cutthroat, and they run big. Twenty inch fish at 10,936 feet is the reason to make this climb.
The climb: steep and rugged, a lot of elevation over a short distance on open rock. This is the one approach in the basin that is genuinely hard rather than just long.
Camping: Marker sits at 10,936 feet on open rock, far above treeline, so no timber, no wind shelter and no firewood. At 13.7 acres there is a reasonable amount of shoreline, and the boulder near the outlet is the only real windbreak up there. Anyone camping here should expect a fully exposed night and plan for it.
