This hike starts at the north end of Swan Lake Flat and goes through a forest and then down the mountain into a large field of tumbled travertine rock.
At the north end of Swan Lake Flat, hike until you reach the sign that says Fawn Pass, and head right to the north. You'll hike through lodgepole pine and Engelmann spruce and then you'll see a couple great views--one of Swan Lake Flat and the surrounding mountains, and then after that, of the area to the north. Hike down the mountain carefully through the Hoodoos. At the end of them, turn around and come back.
From Mammoth Hot Springs, drive south through Golden Gate Canyon and past Rustic Falls until the landscape opens at Swan Lake Flat. Immediately park on your left in the parking lot next to Bunsen Peak. The trail is across the street.
There is one small lot that fills up quite fast. You can also choose to park in a pullout further south of the parking lot.
Yellowstone National Park