Kroenke Lake in the Collegiate Peaks wilderness is a nice hike to a large alpine lake that is popular with hikers and campers alike.
San Isabel National Forest
One of the best parts of Colorado hiking is alpine lakes. The Ptarmigan Lake Trail is a moderate hike full of wildflowers and a great lake.
The hike to the Harvard Lakes in the San Isabel National Forest is a short but steep hike that leads to twin lakes above 10,000 feet.