Mount Flume and Mount Liberty are located in Franconia State Park, at the edge of the Pemigewasset Wilderness. They are often overlooked because neighbors Mount Lincoln and Mount Lafayette as well as the peaks of the Presidential Range attract more attention. While those are all understandably popular, Mount Flume and Mount Liberty are far less crowded and offer very good views and a pleasant hike.
Mount Flume and Mount Liberty are both part of the Pemiloop, but they can be summited without embarking on a 30+ mile backpack. The hike starts at the Flume Trailhead along I-93. A road walk of less than a mile in an open forest of leaf trees leads from the parking area to the start of the actual trail. This trail is beautiful in the fall.
The Flume Slide Trail leads to the summit of Mount Flume. The climb is very gradual initially and crosses a few brooks until about 2,800 feet, where the Flume slide is reached. The trail then becomes quite steep, but it remains in the woods; this section gets icy in colder weather. The slide is a little less than a mile in length, and it eventually leads to the Osseo Trail, one of the main trails of the Pemiloop. At this point, Mount Flume is only a few hundred feet away.
From Mount Flume (4,328 feet), the views of Franconia Notch and of Mount Liberty and the ridge leading to it are excellent. There is plenty of room to sit and relax on a few big rock ledges at the summit or a few dozen feet farther.
After Mount Flume, the Osseo Trail becomes the Franconia Ridge Trail. This trail would also be used to complete the Pemiloop. Mount Liberty lies 1 mile northwest and is reached after a quick descent in a forest of conifer trees and an ascent of 500 vertical feet.
The summit of Mount Liberty (4,459 feet) has even nicer views than Mount Flume. The latter can be seen quite clearly, along with its slides. To the north, however, the Franconia Ridge and Mount Lincoln attracts most of the attention. Looking north, its cone-shaped rocky peak towers above all other mountains.
The descent starts shortly after the summit of Mount Liberty. There are tent platforms at Liberty Springs Campsite, 400 vertical feet below the ridge. The Liberty Springs Trail leads down straight to the paved road used in the first leg of the hike. The descent is gradual, much more so than it would be on the Flume slide. The trail crosses a brook in which water bottles can be refilled (use a filter or tablets).
There might be a few hikers on these trails, especially during summer weekends, but it will not compare to the hundreds that will flock to Mount Lincoln and Mount Lafayette year round.