The Hoover Bridge spans the Colorado River and connects the Clark Country of Nevada and the Mohave Country of Arizona to a part of a 5.6km road construction project. Interestingly, because Nevada and Arizona have an hourly time difference, there is a clock at each end of the Hoover Dam at the dividing line between the two states, showing the time of the two states to facilitate visitors. Adjust the time. At the Hoover Dam, there is a museum dedicated to the history of the Hoover Dam. After the Hoover Dam was built, the first thing the designer did was to build a black monument by the dam. There are a few lines of English inscribed on it, which means that the United States of America will always remember those who are looking for the final rest in the construction of the dam. On the other stone behind the monument, 112 names of workers who sacrificed to build the dam were engraved.