The Garden of the Gods exists today as remnants of differentially eroded bedrock . Differential erosion is defined as selective removal of rock material in accordance to erosive susceptibility and agency . This means that the hardness of rock material is partly related to its ability to withstand erosive forces of wind, water and ice in a particular climate. For example, shale and mudstones erode more easily than sandstone. Denudation is where weathering and erosion wears away and lowers the rocks and land.
Water is by far the most dominant factor.
Even in most arid regions, water is primarily responsible for shaping the land. Shales, mudstones and siltstones will erode to form valleys. If, instead of the arid climate found in the Garden of the Gods, the climate was a moist one of high rain and snow, the towering formations would have deteriorated much more rapidly through time. This happens when water from dew or other precipitation seeps into the rocks, then is drawn back or evaporates, leaving minerals such as iron or manganese oxides.