In 1864 Brigham Young and the settlers in St. George had a plan to bring goods and people up the Colorado River to St. Thomas near Overton. From here they would be taken by wagon through Nevada to Southern UT and on to Salt Lake City. If this plan had taken place, St. George would have a major stop along the way.
The civil war had made travel by train across the North more dangerous and the idea was to sail around South America to California and bypass the conflict. Jacob Hamblin and others were sent to St. Thomas to scout a road from the Colorado River. Eventually, a warehouse was built to house the goods that would be brought up the river.
Of course, this plan never panned out. The end of the civil war made travel through the United States much safer and the coming of the railroad made it much easier to travel to UT without navigating the Colorado and bringing everything in by wagon.
Later when Hoover Dam was built, Lake Mead filled up and over St. Thomas. The town and its ruins have only been seen in the last few years as water receded during the drought. There are some remains of houses and buildings, but most of it has been washed away.
The early settlers of this area were always thinking and working to make things better. I am impressed by their vision and constant optimism. I also wonder how large St. George would be now if it had grown significantly back then.