Gold and silver rushes increased the level of mining activity and settlement in the American West during the nineteenth century. This paper aims to identify the short- and long-run impacts of this activity on population growth and density. We find that, in response to gold and silver site discoveries, areas nearby grew more in population than areas farther away. Many of these newly formed towns eventually died, however, as the mining industry declined. These ghost towns were initially smaller, more isolated from markets, and more dependent on mining than their surviving counterparts. We find that, even though the mining industry had declined considerably by the early twentieth century, today’s western population is still more populous and dense around historical mining sites compared to other areas. Early mining activity thus encouraged growth, decline, and path dependence in the urban system of the western US.