Yellowstone National Park · Idaho, Montana, Wyoming

South Boundary Trail: Grassy Lake-South Entrance

8.1 mi of trail, end to end · about 1,100 ft of climbing · 6,899 ft–7,720 ft · earth surface · trail class Minimally Developed · hiking

6,899 ft 7,570 ft · 6.5 mi high 7,718 ft

Trailheads Beula Lake Trailhead 7,567 ft Drive there · South Boundary West Trailhead 6,899 ft Drive there

On the parks map

Other trails from the same trailheads

All 473 trails in Yellowstone National ParkFind a trailOn the parks mapPark on nps.gov

About this trail's facts

The lines are the National Park Service's public trails layer, the trailheads and the waterfalls, views, peaks and historic places along them the Service's public points of interest, read 2026-10-16 and simplified for the map; the length is the line's, end to end. The write-ups are the Service's own "things to do" 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 park's own site before you go.