Relatively small by today's standards, in 1910 this was the highest dam in the world – a landmark achieved only after epic battles with incompetent contractors, unprecedented flooding and Wyoming's first labor strike. The tiny visitor center, connected to the parking area with a free shuttle, has interesting displays, and you're welcome to walk across the dam and peer down at the historic power plant in the canyon below.
Be sure to check out the massive wooden stopper in the parking lot, once used to plug the spillway.