The Maroon Bells, Colorado still retain a light dusting of snow above the green vegetation at lower elevations. As climate patterns change, the amount of snow in the Roaring Fork Valley and how late into summer it lasts may also change. Credit: Emily Jack-Scott

A stereograph of Elk Lake and Snowmass Mountain in Colorado (displaying the same image side by side) shows the Roaring Fork Valley during the time before removal of the Ute people. Politics, as well as economics or ecology, can shape a landscape. Credit: William H. Jackson, Hayden Survey 1873.

A visitor looks out from the Penny Hot Springs, near Carbondale, Colorado. Tourism drives much of the Roaring Fork Valley's economy, but tourism also can impact the ecosystems that support it. Credit: E. Osenga 2012

A stereograph (showing the same image side by side) of Snowmass Mountain shows a scene from Roaring Fork Valley more than half a century before the development of ski trails. Credit: William H. Jackson, Hayden Survey 1873