Course of the Colorado River into the Virgin River, which ran southward through what is now Overton Arm to join the Colorado River near the now-ghost town of St. Thomas, Nevada. At Hoover Dam, the Colorado turns due south through Black Canyon, a direction it will follow for the remainder of its course to the Gulf of California. It passes under the Mike O'Callaghan–Pat Tillman Memorial Bridge (Hoover Dam Bypass), the highest concrete arch bridge in the world, carrying U.S. Route 93 at a height of above the Colorado River. At the end of Black Canyon the Colorado widens into Lake Mohave, created by the
Steamboats of the Colorado River west side of the river sixty five miles above Fort Mohave near what was then considered the high water limit of navigation. George A. Johnson came up river and made a deal to supply the mines with his steamboats at $100 a ton, a lower price than the $240 a ton charged for overland freight across the Mojave Desert from Los Angeles. That fall news of the strikes brought a flood of miners to the canyon. Several camps were founded in the canyon. San Juan, or Upper Camp were at the top of the canyon, near modern Nelson, Nevada. Midway