This Preserve, established by the Nature Conservancy, protects crystal clear pools and a unique wetland complex at the base of the scenic Aspen Mountains. The cold springs that feed the terraced pools and creek system deposit high concentrations of travertine (calcium carbonate), which gives the site its unique geology. The spring water has been determined to be 13,000 years old. Perhaps the most impressive physical feature is Formation Cave, which is almost 20 feet tall at the entrance and 1,000 feet long. The ponds attract numerous wintering waterfowl and support a healthy trout population. On the Preserve look for mule deer, raptors, and numerous songbirds.