Boss Lake Reservoir is a lake inside of San Isabel National Forest. Access starts in the very small parking lot left of the Monarch snowmobile rentals. There is space for 6 cars. The hike is less than 5 miles RT but it is steep at the end once it crosses the creek.Once parked, one can see the road to the trailhead that has a big sign to Boss Lake and it is also used for Jeeps in the summer.One can hike on the jeep road until it intersects with the trailhead approximately 1 mile and a half from the beginning of the road. The trailhead sign is visible to the left of the road.The trail then becomes part of the Continental Divide trail. Follow it as it contours and crosses the creek and steeply moves up through the forest, past a few down trees and then it levels out and then finally goes up the last steep part before arriving to Boss Lake Reservoir. Please be prepared with enough water and food.. Even though it is a short hike, there is quite a bit of elevation gain from the parking lot to the lake. Enjoy the beauty of the lake as well as Mt. Aetna which is very prominent as you come down towards the creek on your way back from the lake.