Description by the NPS:
"Distance, round trip: 2.5 miles (4 km)
Difficulty: moderately strenuous
Trailhead: At the back of the Biscuit Basin
boardwalk, 2 miles (3.2 km) north of Old
Faithful Junction. You can also begin 0.25
miles/0.4 km south of Biscuit Basin; park in
pullouts on either side of the road."