From Ashton, ID, take State Rt. 47 east 5.3 miles to Yellowstone National Park/Cave Falls sign. Turn right at sign and go 18.3 miles to campground sign. Turn right at sign into campground.
NOTE: After 5.9 miles, the access road enters Targhee National Forest and becomes Forest Rt. 582 with gravel surface. After 16.7 miles, the road becomes paved again upon entering Wyoming. Overall, access to the campground is on RV friendly roads.