Elk Lake (East Rosebud)
Drainage: East Rosebud
Approaches: Approximately 6.5 miles round trip from the East Rosebud trailhead, with roughly 600 feet of climbing.
Elevation: 6,796 feet
Fish: Brook trout, abundant and self-sustaining. Rainbow trout, rare and self-sustaining. Montana FWP.
Coordinates: 45.16454, -109.66004
Bugs: Not a problem in August.
Getting there
Elk is the first lake upstream of East Rosebud Lake on Trail #15, and there is no decision to make along the way. You park at the dead-end, start walking, and the trail delivers you.
The mileage depends on who you ask. FWP calls it 3 miles. The Forest Service calls it 3.5. Our GPS read 3.2 to the shore, which is close enough to call it a bit over three either direction. It is a gentle grade for this range, about 600 feet of climbing spread across the whole thing.
With overnight packs we took roughly an hour and fifty minutes from the car. Day-hikers going light will beat that easily. On a June 10 trip years back there was no snow on it at all, which is early for anything in this wilderness and a good reminder that the lower East Rosebud opens up well before the country above it.
The hike
Here is the thing nobody's guidebook will tell you: as of August 2026, Elk is hardly a lake anymore. The flood took it down.
FWP's 2026 guide still lists it at 7.3 acres, 2 feet average depth and 5 feet at the deepest, so this is not much more than a wide, shallow spot in the creek to begin with. If Elk is your whole objective, know that going in.
What it still is: a pleasant, easy, well-graded three miles with good camping, and the natural first stop for anyone testing legs or gear before committing to the long walk up to Rimrock and Rainbow. The Forest Service calls it a popular day-hiking destination and they are not wrong.
Tips & safety
Navigation: No route-finding. Trail #15 the whole way, first lake you come to. This is a busy trail, so expect company.
Camping: There are campsites at Elk. FWP describes it as nice camping with some firewood available, and that matched what we saw.
Fishing: Brook trout are abundant but small. FWP sampled 12 brookies in 2015 averaging 8.1 inches with the biggest at 10.5, and 16 in 2007 averaging 8.3. Rainbows are rare and have not been stocked since 1948. FWP notes the 2015 set was a poor two-hour daytime net, and one of the two rainbows they got came from two hours of angling. Add the flood to that and set your expectations accordingly.
Bugs: Nothing that stood out.
