They came from the Bay Area, Boulder, Nashville, Tenn., and Denver. They bought old homes, found new communities and then got to work creating. Listening rooms, live music venues, artist residencies, social spaces and live-work co-ops are all parts of the quiet movement happening in Colorado’s San Luis Valley. And if the artists are any indication — and they usually are — then the tiny southern Colorado towns of Saguache and Del Norte, along with more communities down valley, are on the verge of entering our collective imagination. Though, for some, these places have long been cemented. Colorado’s high alpine desert, the San Luis Valley is larger than the state of New Jersey with fewer than 50,000 residents and an outsized concentration of natural wonders — from the Great Sand Dunes to the headwaters of the Rio Grande. This swath of the West once comprised border territory between the U.S.