Grotto Falls drops 20 feet in a single plunge on Roaring Fork in Great Smoky Mountains National Park, Tennessee, and is the only waterfall in the park with a trail passing behind it.
The falls
Lidar mapping puts the drop at about 20 feet, down from an earlier figure of 25 feet. A separate, smaller fall of 10 to 12 feet sits several hundred feet downstream on the same fork.
Getting there
The hike starts at the Trillium Gap Trailhead, two miles in on the one-way Roaring Fork Motor Nature Trail, and covers 2.6 miles round trip on a well-traveled route with stream crossings. Parking at the trailhead is limited. The park charges no entrance fee, but parking for more than 15 minutes requires a $5 daily, $15 weekly or $40 annual tag. A longer, 5.4-mile route continuing past the falls toward Mount Le Conte is rated moderately strenuous.
When to go
The trail is especially busy in summer and can turn muddy and slippery after rain or high water.
On site
The trail passes directly behind the main fall. As of September 2026, the park's closures page listed the Trillium Gap area under a bear warning rather than a closure, and a mowing closure on the motor nature trail that month was announced as leaving the trailhead itself open. Swimming and dog rules for this stretch are not documented.
History and name
The name comes from a cave-like sandstone formation at the falls.
Nearby
Upper Grotto Falls is about 0.3 mile away, Twin Falls about 0.9 mile, Dome Cascade about 1 mile, and Rainbow Falls about 1.1 miles.
Distances are straight-line.