Ptarmigan Pass (Front Range)

Tyndall Glacier is a small cirque glacier in Rocky Mountain National Park in the U.S. state of Colorado. Tyndall Glacier is on the east side of the Continental Divide and in a cirque to the north of Hallett Peak. Tyndall Glacier is both an ice and a rock glacier, with the lower portions of the glacier being composed primarily of rock debris and a small portion of ice. Tyndall Glacier is named after John Tyndall, an Irish scientist and Alpine mountaineer who in 1861 first ascended the Weisshorn in 1861. He also made an early attempt on the Matterhorn prior to its first ascent. In 1861, Tyndall identified carbon dioxide as a heat-trapping greenhouse gas; the glacier that bears his name appears to be retreating.

The High Rockies, or high country, is a term for a region of the U.S. state of Colorado. It commonly includes Larimer County, Jackson County, Routt County, Grand County, Summit County, Eagle County, Lake County, and Pitkin County. Some notable towns there include Estes Park, Walden, Steamboat Springs, Grand Lake, Winter Park, Breckenridge, Dillon, Vail, Leadville, and Aspen. The geography of the High Rockies has some of the most rugged parts of the Rocky Mountains and consists of the Front Range and mountainous topography to the west, much of which is on or near the Continental Divide. Known for pine forests and winding roads, the former mining towns there have been reinvented by wilderness tourism such as hiking, cycling, fishing, and most especially both cross-country and alpine skiing. Notable ski resorts include Copper Mountain, Keystone Resort, Steamboat Ski Resort, Beaver Creek Resort, Buttermilk, Aspen Highlands, Snowmass, and Aspen Mountain. The High Rockies are also the location of Rocky Mountain National Park and Arapaho National Forest.

Hidden River is a tributary of Spruce Creek in Larimer County, Colorado. The stream's source is near the summit of Stones Peak in Rocky Mountain National Park. It flows southeast to a confluence with Spruce Creek in Spruce Canyon.

Fern Lake is an alpine lake in Larimer County, Colorado, United States. It is a major source for the Big Thompson River.

The Fern Lake Patrol Cabin in Rocky Mountain National Park was designed by National Park Service landscape Daniel Ray Hull and built in 1925. The National Park Service Rustic cabin was used for a time as a ranger station. It was destroyed by the East Troublesome Fire in 2020. It was listed on the National Register of Historic Places in 1988, and was delisted in 2022, after being destroyed by the East Troublesome Fire.

Dream Lake is a high alpine lake located in Rocky Mountain National Park in northern Colorado, located east of the continental divide. The lake is at the base of Hallett Peak and access is via the Bear Lake trail head. It is known for its views caused by surrounding steep cliffs, and is a destination for casual hiking.