Hike a 7.5-mile loop from Horseshoe Lake Campground with a side trip to views of South Cascade peaks from the summit of Green Mountain.
From the Horseshoe Lake Campground, at the faded sign on the trail that says “Trail,” take a short connector to signed High Lakes Trail No. 116. Turn right and hike 0.5 mile to the junction with Keenes Trail No. 120. Turn left and hike northwest for 1.2 miles to the junction with Spring Creek Trail No. 115. Watch for an exceptionally large Douglas-fir on the left just before the trail junction.
Turn left on Spring Creek Trail No. 115 and in just 75 feet, find the junction with Green Mountain Trail No. 110. You have now walked 1.7 miles. Follow the trail as it crosses some small creeks on wooden bridges marked by signs saying they were built by motorized recreationists. The trail then begins to climb the slope of the mountain. The trail switchbacks, gradually but steadily climbing through dry Douglas-fir forest. The trail passes the edges of several balds that give views to the crest of the South Cascades to the northeast and east. Look for landmarks like Potato Hill and Lakeview Mountain at the south end of the Goat Rocks.
The balds host wildflowers in early summer, so take a break to look around.
When the trail turns west, the junction with the spur trail to the summit is coming up. At 2.0 miles, take a short (0.2 mile) spur trail to the Green Mountain summit. Play “name that peak” as you check out the views in different directions from the summit. Mount Rainier rises above the shoulders of Hamilton Buttes while the Cispus River valley below draws your eyes to its headwaters at Cispus Basin in the Goat Rocks. Mount Adams and Mount St. Helens beg for attention.
Look down at your feet for wildflower displays including Cascade Aster, Northern Buckwheat, Sulphurflower Buckwheat, Subalpine Mariposa, Columbia Tiger Lily, Broadleaf Lupine, Spreading Phlox and Beargrass.
When you have enjoyed the vista, return the way you came to the junction with Spring Creek Trail No. 115. Turn right and go 1.1 miles, passing Green Mountain Lake on your right, to the junction with High Lakes Trail No. 116.
Turn left on Trail No. 116 and soon spy a marshy corner of Horseshoe Lake on your right. Walk about 0.2 mile to the junction with the unsigned connector trail back to the campground on your right.
WTA Pro Tip: Since these trails are open to horses, mountain bikes and motorcycles, hike mid-week for solitude. Mosquitoes can be bad in July.
For a slightly shorter, in-and-out version of this hike, start on the connector trail from Horseshoe Lake Campground, turn left at the first intersection on High Lakes Trail No. 116, go 0.2 mile to the junction with Spring Creek Trail No. 115. Turn right and hike 1.1 miles to the junction with the Green Mountain Trail No. 110. Hike to the summit and return the way you came for a total distance of 7 miles.