From WikiGTA - The Complete Grand Theft Auto Walkthrough
Las Barrancas is a village close to the Sherman Dam in Bone County, San Andreas. The name 'Las Barrancas' is Spanish and means 'The Ravines'. This is probably a reference to the legend of colonel Henry Bolt, a colonel of the 66th Cavalry who in 1842 with his whole legion fell into a ravin when he came to help a town which was besieged by bandits. Some claim to hear at night the sound of hundreds of troting horses.
In the rock to the east of the village a Hopi ruin can be found.