Pneumonia Lake
Difficulty: Hard
Trip Type: Multi-Day Backpacking / High-Alpine Route
Distance: ~5.7 miles from starting trailhead / ~0.5 miles from Splinter Lake Basecamp
Elevation: 9,863 feet
Coordinates: 45.09745, -109.84403
Time: ~30 minutes from Splinter Lake Basecamp
Access: Demanding off-trail climbing. Departs from Splinter Lake Basecamp.
Bugs: Minimal (little to no bugs)
Getting there
The multi-day backpacking route departs from the Lady of the Lake Trailhead. Please note that this is a thru-hike itinerary; our group dropped one vehicle off at the Beaten Path Trailhead first, then jumped in the truck and drove over to the Lady of the Lake Trailhead to begin hiking. This ensures a vehicle is waiting for pickup at the other side when you finish the trip.
The hike
If you are traveling straight from the vehicle turnaround, the route to Pneumonia Lake spans roughly 5.7 miles from the starting trailhead and involves almost 1,650 vertical feet of elevation gain. For backpackers tracking directly from your multi-day basecamp, this destination sits about 827 yards past camp at Splinter Lake.
This leg initiates Day 2 of the backcountry loop. Following the drainage straight up from your Splinter Lake campsite makes it relatively easy to navigate the steep terrain to reach Pneumonia Lake, which involves a 450-foot vertical climb from basecamp. This is a beautiful body of water where you will be treated to sweeping, unobstructed views of the Cathedral Spires stretching high above the valley.
Tips & safety
High Country Weather: Because this lake sits high up in the open drainage, it is highly exposed to passing alpine fronts. Plan your clothing layers accordingly, as storms can strike this upper shelf rapidly.
Thru-Hike Logistics: Because this extended itinerary finishes at a completely different exit point, ensure your logistics are arranged with a shuttle vehicle waiting at the final trailhead before you set out.
Fishing: No fish species information is listed in official Montana Fish, Wildlife & Parks data guides.
