The Flatirons are rock formations in the western United States, near Boulder, Colorado, consisting of flatirons. There are five large, numbered Flatirons ranging from north to south along the east slope of Green Mountain, and the term "The Flatirons" sometimes refers to these five alone. Numerous additional named Flatirons are on the southern part of Green Mountain, Bear Peak, and among the surrounding foothills.

Red Rocks Amphitheatre is an open-air amphitheatre in the western United States near Morrison, Colorado, approximately ten miles (16 km) southwest of Denver, which owns and operates it. In addition to several other large sandstone formations nearby, the venue is best recognized by its two massive monoliths, named "Ship Rock" and "Creation Rock", as well as the smaller "Stage Rock", which together flank its 9,525 capacity seating area and naturally form the amphitheater. While the venue is primarily known for hosting concerts and music festivals, other events of various types and sizes are held throughout the year.