Windsor Lake is a really popular hiking destination just outside of Leadville, Colorado, but it can work well as a shorter run, too (or an addition to a longer run). After a short, steep climb, you are rewarded with access to two alpine lakes (one small pool and one larger) situated right at treeline (a little over 11,600 feet). While fairly short, the trail to the lake is not the easiest and feels longer than the distance implies.