Smarts Mountain is a moderately difficult hike in the Upper Valley, offering two options for reaching its summit. From the small trailhead, the white-marked Appalachian Trail is the main route, gaining elevation quickly and traversing Lambert Ridge. Views may be had along the ridge, and hikers can admire the beauty of the quartzite ledges found along the way. For a more gradual ascent or descent, the Ranger Trail is marked with blue paint and is an unmaintained, lesser-traveled route. Some choose to go up the Appalachian Trail and return via the Ranger Trail to make a loop.
The summit of Smarts Mountain is wooded, but a 360-degree view can be found from the 41-foot fire tower. From the tower, the Dartmouth Skiway, Reservoir Pond, Mount Cardigan and Mount Kearsarge can be seen. In the early 1900s, two wooden towers stood on Smarts Mountain for fire observation, but they became inactive in 1922 due to communication issues because telephone lines were too frequently damaged. Today you can find remnants of the old telephone poles along the Ranger Trail. Shortly after its closing, the Dartmouth Outing Club cut trails on Smarts and replaced the tower and cabin. The tower was staffed on and off until the 1970s. In 2016, the fire tower and ranger cabin were both restored, and the ranger cabin now provides shelter for AT hikers.