ASPEN, Colo. —  In Aspen, the wealth gap is geographic.

The people who clean the vacation homes, maintain the mansions’ gardens and work in the hotels must find housing in mobile home parks or subdivisions squeezed into the few acres of developable space dozens of miles to the west.

Meanwhile, residents who struggle to find affordable real estate watch an increasing number of houses in town become rarely inhabited vacation properties.

Aspen’s dilemma is similar to that of other resort towns _ from Nantucket, Massachusetts, to Park City, Utah. In the West, vast tracts of public land and sheer mountain faces prevent the easy development of suburbs to house workers, pushing clusters of more affordable housing into pockets of developable land many miles away.