The Emerald Lake Trail in Rocky Mountain National Park near Estes Park, Colorado, is probably one of the most popular day hikes because of its spectacular alpine scenery. The basic trail goes past three lakes-Nymph Lake, Dream Lake, and Emerald Lake-with side trails to Bear Lake and Lake Haiyaha.
It is a relatively easy hike, with 3.2 miles round-trip and considerable elevation gain, making this hike suitable for families and beginners alike. This is the home of considerable wildlife-one may see elk and chipmunks. The emerald-green waters perfectly reflect the surrounding mountains at Emerald Lake, especially in the early morning.
Bear Lake Trailhead is the starting point of the trail, and this is car- and park shuttle-accessible. It is necessary to have timed entry permits and/or national park passes to access it. It's open all year, but the best time to come is between May and October.