Caves
Colorado has many caves, most of them carved by underground water in Paleozoic limestone. The Cave of the Winds at Manitou is the only one in the state which has been developed as a tourist attraction. It is in highly faulted Ordovician and Mississippian limestone near the mountain front, where the faulting, coupled with the high relief, has accelerated solution of the rock by allowing groundwater to percolate downward rapidly. The cavern was probably carved during the Pleistocene Ice Age, when surface water and groundwater were much more abundant than at present. Deposition of [stalactites] and [stalagmites] has occurred within the last few thousand years, as supplies and movement of water have decreased.
Spanish Cave, above timberline on Marble Mountain in the Sangre de Cristo Range, is probably the nation’s highest limestone cave. It is in thick folded and faulted Pennsylvanian [reef] limestone, at an elevation of over 12,000 feet. The cave has many intricate passageways branching from its main vertical tubes and channels.
Fulford Cave, south of Eagle, is in the Mississippian Leadville Limestone of the northern part of the Sawatch Range. Many other caves are situated south of Fulford, near Woods Lake, where the limestone is widely exposed and highly dissected.
Fairy Cave, northeast of Glenwood Springs, is the best known of the many caverns in the Paleozoic limestones that form the southern flanks of the White River [Plateau].
In Cave of the Winds near Manitou, Paleozoic limestones, cracked and tilted by uplift of the Front Range, have been honeycombed by ground water. Calcite [stalactites] hang from the ceiling, while [stalagmites] grow up from the floor. (Cave of the Winds Company photo)
In the [Plateau] Province another type of cave is formed not so much by groundwater as by weathering of the flat-lying alternating beds of massive resistant sandstone and less resistant, thinly bedded mudstone and shale. Where the resistant layers are undermined, great arching caves develop. These are best observed at [Mesa] Verde National Park, where many of them once sheltered Indian communities. They can also be seen in Colorado National Monument and along the Colorado River and several of its major tributaries.
Along the edge at [Mesa] Verde, caves in Cretaceous Mesa Verde sandstone were used for shelter by Indians. Springs near the bases of the caves, which provided the Indian communities with water, probably contributed to the undermining of the sandstone cliffs. (Colorado Department of Highways photo)