This is a fabulous hike: It is not too congested, and it takes you to some gorgeous alpine lakes. Both Tower Lake and Rockbound Lake are stunning with their deep colors and great scenery. It is best in late-spring and summer, as snow stays late into the season and can make the trail impassable.
Begin at the parking lot and follow the old road trail as it narrows and winds up switchbacks. The forest is quiet and idyllic, a fantastic setting for an early morning hike. Grind up the switchbacks and continue until you reach an open meadow after about 5 kilometers of walking.
Once in the meadow, look around you, as you'll be entering at the bottom of a horseshoe-shaped basin with rocky ridges above you on all sides, except the direction from which you just came. On your left is Eisenhower Tower, a large monolith accessible only by trad climbing. Continue through the meadow as the trail winds around fallen trees and foliage.
The meadow opens up to Tower Lake, which rests below Rockbound Lake. Tower Lake is a magnificent green, and it is the perfect place to rest before tackling the final push to Rockbound Lake.
On the right side of Tower Lake the trail continues toward Rockbound, meeting the headwall below the upper lake after a few hundred meters. The headwall features a series of steep switchbacks. Push past these, finishing the vertical element of the hike, and walk through a small grove of trees toward Rockbound Lake. Stuart Knob (2,850 meters) stands opposite the crystal blue lake.
Rockbound Lake is aptly named. It is surrounded by giant boulders and sheer limestone cliffs on all sides. Some of these boulders are great for avid climbers, though hauling a crash pad 8.5 kilometers to the lake is a hassle. If you do chose to climb, make sure you have a spotter!
Rockbound Lake also has decent brown trout fishing, so you may be rewarded if you bring a rod all the way to the lake!
You can walk around the lake in all directions, but if you continue on the right side and ascend the at the back of the lake, the trail leads 2.5 kilometers away to a great vantage point above the lake. You can continue around the ridge to the left to summit Castle Mountain or head farther out (make sure you have a map and know where you're headed).
Note that there can be bear restrictions on this trail because this is grizzly country.