Really enjoyable flat hike that takes you through old railroad tunnels that were used to build Hoover Dam. We parked at the Lake Mead Visitor's Center side and didn't do the whole trail, but you can go all the way to the Hoover Dam. The tunnels are really interesting to see and yes you see there really is a light at the end of the tunnel! Awesome views of Lake Mead as you hike. Check this place out for a fun but not too intense hike and bring a bottle of water.