Island Park, ID

Island Park is a high-altitude gateway community in eastern Idaho, sitting 20 miles from Yellowstone's west entrance at 6,200 feet elevation. Highway 20 runs straight through town, connecting visitors from Idaho Falls (80 miles southwest) and providing direct access to West Yellowstone, Montana. The town stretches 33 miles along the highway, officially making it the longest main street in America, though most of that distance passes through undeveloped forest between scattered lodges and cabins.