If you’re looking for a place to chill on a hot summer day, Keystone’s mountaintop sledding venue might be hard to beat. Although it’s been in the 80s, 90s and 100s on the Front Range, there’s plenty of snow at the top of Dercum Mountain, at an elevation of 11,640 feet, and resort officials say their summer sledding operation is the only one of its kind in the U.S. It’s a pretty ingenious repurposing of resort assets.