The Little River flows parallel to the road through Townsend, and it's wonderful for tubing. There are several tubing rental/shuttle companies along the way (River Rat, River Rage, and Cowboy.) Check with the various companies, as there are faster, more exciting sections and there are very long, peaceful floats.
We have stayed at Big Meadow CG (River Rat Tubing right next door) and the KOA. We enjoyed both places. Big Meadow is a bit stricter rule-wise and does not have fire pits at the sites, but it is very quiet. The CG is actually across a small road from the river, so it isn't what I would call true riverfront, but it is darn close. The KOA FHU sites were very close together, but did have decks at each site. It was a bit noisier there due to more kids, but not bad. Both CG's had nice swimming holes.
Tremont is also very popular, but we have never stayed there (drove through and got brochures and it appeared very nice as well.)
The Townsend area is beautiful and quiet. It is right at the entrance to the park, and close to Cades Cove, etc.. We also like the convenience of Wears Valley Road as a quiet "shortcut" up to Pigeon Forge for when we want to shop or eat at restaurants (although there are several very good restaurants right in Townsend.)
If you want away from the craziness/traffic and want to be close to the rivers, trails, and scenery of the park, then Townsend is perfect.
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