The 2.7-mile (one-way) hike to Rainbow Falls in Great Smoky Mountains National Park is almost entirely uphill. The trail gains close to 1,700 feet in under 3 miles. However, the trek to Rainbow Falls is well worth the effort, especially since the overall mileage is rather low.
On the way to Rainbow Falls, LeConte Creek cascades along the right side of the trail for almost the entire duration of the hike. There are two creek crossings on the way, as well as plenty of great picnic sites to stop hiking, relax, and have a snack.
Rainbow Falls are the highest single-drop waterfalls in the Great Smoky Mountains National Park. If you're lucky, you will visit on a day when the mist created by the waterfall interacts with the sunlight shining through the trees. This effect creates the frequent rainbows seen by the falls and is the reason the falls were given its name. The falls are best viewed during or after long periods of rain because this is when the waterfall displays its most powerful flows.
If hiking to Rainbow Falls itself isn't enough, the trail continues for another 4.2 miles to the famous summit of Mount LeConte, the third-highest peak in the Smoky Mountains.