Boulder City was built in the 1930s to house the workers constructing Hoover Dam, and it has kept its small-town character ever since — it is the only city in Nevada where gambling is illegal. The historic downtown has a pleasant main street with diners, antique shops, and a small museum about the dam's construction. The Boulder Dam Hotel, a handsome Dutch Colonial building from 1933, still operates.
The main reason to stop here is Hoover Dam itself, just a few minutes south of town. But Boulder City also sits at the edge of Lake Mead National Recreation Area, with access to kayaking, hiking, and swimming in the desert. The Historic Railroad Trail follows the old construction railway through tunnels blasted out of the rock, with views of the lake. It is a more interesting base than Las Vegas if you want to explore the desert and the dam without the noise.