Shoshone Falls drops 212 feet over a curved basalt lip about three miles east of downtown Twin Falls, making it the highest major waterfall in the United States. The volume varies enormously with the season: in spring, when snowmelt fills the Snake River, the falls thunder across the full 900-foot-wide rim and the mist reaches the viewing platforms. By late summer, irrigation draws so much water from the river that the falls can slow to a comparative trickle — plan your visit between April and June for the full effect.
The park sits on the canyon rim above the falls with well-positioned viewing platforms. There's a modest day-use fee. The walk from the parking area to the main overlook is short and paved, but side trails allow you to get closer to the basalt rock faces and the plunge pool below. The canyon setting is dramatic even when the water is low — the walls drop steeply and the black volcanic rock has a raw, geological character quite unlike the polished limestone of eastern waterfalls.