Turbid Springs, Yellowstone National Park: small groups of mud pots and sulphurous pools along the southeast edge of Turbid Lake, reached by a 5 mile hike from the Pelican Valley trailhead, or a 3.5 mile hike from Lake Butte. Away from the springs, much of the lake is enclosed by mud flats and dead trees, and the surrounding hills are home to an active grizzly bear population. (mp4; 0:50 min; 16 mb)