"In 1931 the federal government undertook the building of what was then the largest dam in the United States. While the dam remains, much of the roads and trails used to access the construction site have long since disappeared—that is, except for the Historic Railroad Trail. This trail not only offers unique views of the lake, but also allows you to pass through the very tunnels used by the railroad when traveling to the dam.
These trails are only open to human power and are used by mountain bikers, hikers, and runners. The road is wide enough to easily offer room for everyone on the trail. Here you may spot owls, bighorn sheep, coyotes, and bats. In fact, Mexican free-tailed bats roost in many of the tunnels. If you ride in the evening, you can often see the bats fluttering around. Bats, and all other wildlife, should be left alone."