Mallory Cave was first discovered, but not recorded, by loggers cutting down trees on Dinosaur Mountain in the early 1900s. The cave, only a rumor at the time, was 'rediscovered' by University of Colorado Student E.C. Mallory in the summer of 1932. The cave is of special importance to Fringed Myotis and Townsend's Big Eared bats, whose maternity colonies roost here between April and October.

Red hues in the Fountain Formation - of which the Flatirons, Sanitas Ridge and Settlers Park rocks are all comprised - are the result of iron oxidation in its composite layers

The Fountain Formation was originally laid down flat, but thrust steeply upwards during the Cenozoic Time

Mule deer have relatively small rumen for their body size, which makes them more selective foragers than larger ruminants

Bear Peak (8,461') emerges to the south across open grassy slopes just before reaching the Mallory Cave Trail split

Ponderosa bark turns from dark brown-black to its distinctive cinnamon-red color at about 90 years of age

Even during periods of heavy snow cover, the Mesa Trail sees heavy traffic and is easy to follow up to the Mallory Cave Trail split

Townsend's Bats are distinguished by very large ears and glandular lumps on either side of its nose

A red fox hunts along the Mesa Trail's grassy slopes

View of NCAR, the National Center for Atmospheric Research

Bear Peak and Dinosaur Mountain before the split for Mallory Cave

Bull snakes, which can reach 6', are common in the Boulder foothills and high eastern plains

Mallory Cave is well hidden among steep folds and vertical rock faces of the Flatirons

Lingering ice and snow can make the final climb a precarious task

White Nose Syndrome (WNS) affecting bats is considered to have caused the greatest wildlife decline in the past century in North America - hikers are no longer permitted in Mallory Cave