Overview
Fourmile Lake sits at 5,756 feet beneath the dramatic east face of Mount McLoughlin (9,495 ft) in the Sky Lakes Wilderness of Fremont-Winema National Forest. The lake is accessible from a well-developed campground and serves as the most straightforward entry point into the Sky Lakes Wilderness from the Klamath Falls side.
The trail from the campground enters the wilderness immediately and climbs 2.6 miles to a high point with views of the wilderness interior before the natural turnaround for a day hike. Fourmile Lake itself is a destination worth spending time at: the reflection of Mount McLoughlin in the lake surface on calm mornings is one of the more photographed scenes in southern Oregon.
The Route
Fourmile Lake Campground to Wilderness Boundary (Mile 0 to 0.5)
The trail departs from the upper end of the Fourmile Lake Campground and enters the Sky Lakes Wilderness within the first half mile. The boundary is marked with a wooden wilderness boundary sign.
Wilderness Trail to High Point (Mile 0.5 to 2.6)
The trail climbs through mountain hemlock and Shasta red fir, gaining elevation consistently. At the high point at mile 2.6, views open south and east across the wilderness interior toward the lake cluster of the Sky Lakes basin.
The turnaround is at this high point for the day hike. Continue further for backpacking access to the main Sky Lakes cluster.
Return via the same route.
When to Hike
July through September is the primary season. The trail is typically accessible by late June in average snow years.
August is ideal for Fourmile Lake photography: calm mornings produce the best McLoughlin reflections.
What to Bring
Many hikers carry 1.5 liters of water. Fourmile Lake provides water at the start of the trail; treat or filter. The wilderness trail sections also have water sources.
A fishing license is needed for fishing in Fourmile Lake.
Trailhead Access
The Fourmile Lake Campground trailhead is on Forest Road 3661 off Highway 140, approximately 40 miles west of Klamath Falls. A Northwest Forest Pass is required for parking (as of 2026). Vault restrooms at the campground.
No wilderness entry permit required as of 2026. Dogs allowed on leash.
Nearby
The Sky Lakes Wilderness Trail from the Cold Springs Trailhead accesses the same wilderness from a different approach with slightly different lake emphasis. The Aspen Butte Trail is accessible from the same Highway 140 corridor for a more demanding summit option.
Check current conditions at Checking Conditions Before You Go. Practice Leave No Trace 7 Principles around the lake margins and in the Sky Lakes Wilderness.