78 of the 100 highest peaks in the Rockies are in which U.S. state?

The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch 3,000 mi (4,800 km) in straight-line distance from the northernmost part of western Canada, to New Mexico in the southwestern United States.

Of the 100 highest peaks with a topographical prominence of at least 500 meters in the Rocky Mountains, 78 (including the 30 highest) are located in Colorado, ten in Wyoming, six in New Mexico, three in Montana, and one in Utah. Public parks and forest lands protect much of the mountain range, and they are popular tourist destinations, especially for hiking, camping, mountaineering, fishing, hunting, mountain biking, snowmobiling, skiing, and snowboarding.

The Rocky Mountains formed 80 million to 55 million years ago during the Laramide orogeny, in which a number of plates began sliding underneath the North American plate. The angle of subduction was shallow, resulting in a broad belt of mountains running down western North America. Since then, further tectonic activity and erosion by glaciers have sculpted the Rockies into dramatic peaks and valleys.