Near the Cabinet Gorge Dam, you'll find a nice area to take a river walk. This area provides almost two miles of trails with amazing views of the Clark Fork River.
Take the turnoff from Highway 200 and you'll find a parking area. From here you'll find trails that follow the river in either direction. By heading west from the parking lot, you'll follow the trail a bit and search slightly off trail for this cache.
Be sure to check out my other nearby cache in the other direction when you're here.