Just south of the town of Estes Park, Lily Lake is a pretty spot, with the lake just below a large rocky outcrop. The trail around the shore of the lake is an easy stroll, but the alternate Lily Ridge Trail involves ascending the rocky ridge to the left. The slope does not look too imposing, yet it starts at 8959 ft (2730m), and at the upper level reaches 9175 ft (2796m). At those altitudes the air has less oxygen, and there is definitely some huffing and puffing during the climb