Mountain "irons" in Colorado

Irons are a series of wedge-shaped cliffs near Boulder, Colorado, United States. On the eastern slope of Mount Green Mount, if we move from north to south, there are five such irons.

These irons are so woven into the history of the area, which are considered a symbol of the town of Boulder. As you know, the name of these rocks was chosen on purpose. Surface really remind soleplate raised sharp angles up. Breed these slopes formed about 290 million years ago. The slope of the same was acquired irons about 80 million years ago. Subsequently, due to erosion, there was such a smooth surface, which attracts hundreds of climbers.