Black Hills National Forest · South Dakota, Wyoming

Deerfield Lake Loop

11 mi loop · about 1,400 ft of climbing · 5,798 ft–6,243 ft · native material surface · trail No. 40L · trail class 3 · typical grade 12-20% · tread 24-36 inches wide · hiking, horse, bike

Picnic areas

6,024 ft 6,028 ft · 11 mi high 6,227 ft

Along the way Mountain City Picnic Area

Trailheads Deerfield Lake Loop Trailheads (Trail #40L) 5,956 ft Drive there · Gold Run Trailhead 5,919 ft Drive there

Deerfield Lake Loop Trailheads (Trail #40L) the Forest Service's write-up

This 10 mile trail encircles Deerfield Lake. From Reynolds Prairie you'll have great views of the lake. To the south, the trail winds through areas of tall pines and small meadows. This trail can be accessed from four trailheads: Custer Trail Trailhead, North Shore Trailhead, Hill Top Trailhead and the Gold Run Trailhead.

This trailhead on fs.usda.gov

Hike this trailAll 535 trails in Black Hills National ForestFind a trailForest on fs.usda.gov

About this trail's facts

The lines are the US Forest Service's National Forest System trails layer (public domain), read 2026-10-16 and simplified for the map; the length is the line's, end to end, and the class, surface, grade and tread width are the forest's own entries where it publishes them - a forest that publishes the centreline alone has none. The trailheads and the points along the way are the Service's recreation points, and the write-ups its own recarea text, unedited. Heights come from USGS 3DEP through Terrain Tiles on AWS (Mapzen/Tilezen), read along each line and rounded; a short trail on steep ground can be off by a few tens of feet. Closures change: check the forest's own site before you go.