Summit Lake Trail

Summit Lake Trail is a 15.4-mile point-to-point section of the Continental Divide Trail, from its junction with Mystic Falls Trail above Biscuit Basin to the western junction where the named path meets a mapped National Forest track. It is a long, remote walk through lodgepole pine and scattered meadows, with Summit Lake and Smoke Jumper Hot Springs along the way. The connected named path measures about 15.4 miles one way; the park’s published 14.5-mile figure does not say exactly where it ends, and a farther boundary extension is described at 16.5 miles but cannot be traced from the available route line. The mapped endpoint is not a verified vehicle exit.

The trail begins after a short approach from Biscuit Basin, then fords Little Firehole River and climbs roughly 600 feet in its first 1.1 miles onto Madison Plateau. The ford can be the deciding part early in the season; water depth changes, so don’t count on crossing when it is high. Near the top, gaps in the trees give intermittent views east toward Upper Geyser Basin. After that first push, the grade eases but keeps climbing for several miles.

Lodgepole forest, pockets of spruce and fir, and occasional meadows lead to Summit Lake at about mile 7.5. It is a fishless lake of a little over 28 acres, with a maximum depth of 21 feet, high at 8,552 feet. The Continental Divide is less than half a mile away and comes at about mile 8; Smoke Jumper Hot Springs sits just west of it. The springs are partly dry. Their name dates to the 1950s, when Yellowstone firefighters used backcountry thermal areas as landmarks while parachuting to fires.

For a day hike from Biscuit Basin, reaching Summit Lake and returning is about 15 miles round trip; going on to the Divide and springs makes it roughly 16 miles round trip. The trail continues west beyond those features through a longer, less varied forest stretch. Treat the full mapped line as a one-way CDT route, not a loop, and arrange a genuine exit before relying on the far-end track. Overnight camping requires a permit. Pets are not allowed, and stay on established paths around thermal ground.