Boulder Canyon (Colorado River) steamboats as they passed over the dangerous rapids of Devil's Gate Canyon, during their high water runs to the mouth of the Virgin River at Rioville, Nevada. Boulder Canyon (Colorado River) Boulder Canyon, originally Devils Gate Canyon, is a canyon on the Colorado River, above Hoover Dam, now flooded by Lake Mead. It lies between Clark County, Nevada and Mohave County, Arizona. It heads at western end of the Virgin River Basin of Lake Mead, at about . Boulder Canyon divides the Black Mountains into the Black Mountains of Arizona, and the Black Mountains of Nevada. Its mouth is now
The Church of Jesus Christ of Latter-day Saints in Arizona Spring, Beaver Dam and neighboring Littlefield, and Lee's Ferry, all in the area between the Utah border and the Grand Canyon known as the Arizona Strip. The first effort at large-scale LDS colonization came in March 1873 when a group of Latter-day Saints was sent from Utah to the Little Colorado River drainage under the direction of Horton D. Height. The colonizers turned back, discouraged by the poor prospects, but a few returned the following year and began farming among the Native Americans at Moencopi. Local hostilities forced the colonists to leave again after a month. A year later, James