Summit Lake Park, National Natural Landmark and alpine park in Clear Creek County, Colorado, USA

Summit Lake Park is a protected alpine area on the summit plateau of Mount Blue Sky in Colorado, sitting at around 13,000 feet (about 4,000 meters) above sea level. The park covers alpine tundra, a small glacial lake, and rocky outcrops, and is listed both on the National Register of Historic Places and as a National Natural Landmark.

The area was added to the Denver Mountain Parks system in 1924, a network the city of Denver began assembling in the late 1800s to protect natural land around the city. It later received National Natural Landmark status in 1965.

The park takes its name from Summit Lake, a tarn that forms the headwaters of Bear Creek. The lake sits in a glacial cirque on the north face of Mount Blue Sky and the east face of Mount Spalding. Fishing from the lakeshore is the only permitted recreation, as swimming is not allowed and hiking is not possible.

The park is reached via Mount Blue Sky Road, which becomes partly unpaved at higher elevations and can be difficult in bad weather. Warm layers are a must, since conditions at this altitude can shift quickly and without warning.

Summit Lake is a tarn in a glacial cirque on the north face of Mount Blue Sky and the east face of Mount Spalding. A col at 12,855 feet to the north looks down into two cirques holding the Chicago Lakes, headwaters of Chicago Creek. A 1915 USGS report gave the lake's elevation as 12,740 feet and called it Colorado's highest.