Castle Rock is a

butte In geomorphology, a butte ( ) is an isolated hill with steep, often vertical sides and a small, relatively flat top; buttes are smaller landforms than mesas, plateaus, and table (landform), tablelands. The word ''butte'' comes from the French l ...

in the Colorado Piedmont region of the

Great Plains The Great Plains is a broad expanse of plain, flatland in North America. The region stretches east of the Rocky Mountains, much of it covered in prairie, steppe, and grassland. They are the western part of the Interior Plains, which include th ...

. An area landmark, it is the namesake of the town of

Castle Rock, Colorado Castle Rock is a home rule town that is the county seat and the most-populous municipality of Douglas County, Colorado, United States. The town’s population was 73,158 at the 2020 census, a 51.68% increase since the 2010 census. Castle Ro ...

. The mesa’s caprock consists of

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture (geology), texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained matri ...

, rock which is strongly resistant to erosion. About 58 million years ago, a volcanic eruption took place that covered the area around Castle Rock with of rhyolite. After a few million years, mass flooding and erosion of the volcanic rock gave way to the butte-shaped mesa that almost resembles plateau. Public hiking trails on the mesa are in Rock Park, at the intersection of Front Street and Canyon Drive in the town of Castle Rock. The trailhead and parking are about two blocks south of the intersection on Front Street, for a 1.4-mile round-trip hike to the base of the town's namesake (climbing the rest of the way to the summit is discouraged by a sign warning that the loose rocks are a fall hazard). Other trailheads can be found along Canyon Drive and Sunset Drive.Day Hikes Near Denver: Castle Rock Trail
8 Mar 2018.

References

Castle Rock, Colorado Rock formations of Colorado Landforms of Douglas County, Colorado Buttes of Colorado {{colorado-geo-stub