This is an excellent backpacking loop trip through the eastern Eagles Nest Wilderness, about 25 miles north of Silverthorne, Colorado (fairly near Denver). Totaling 14.6 miles, the only difficulty may be encountered on the climb out of the trailhead up to Eaglesmere Lake. Also, given that the trail is near Denver, significant numbers of people may be on the trails.
The Eaglesmere Trailhead is approximately 25 miles north of Silverthorne, Colorado in the Eagles Nest Wilderness. Trailhead elevation is approximately 8,700′ and high camp on day 2 at Upper Cataract Lake is around 10,770′. Total loop distance is approximately 14.6 miles in 2+ days of hiking (3.5/5.5/5.6). A guy named Dondo has some interesting photo in his blog post about the area which you can see here. Fishing in the alpine lakes in this loop has been known to be fairly good.