The Boulder Loop Trail makes a three-mile circuit over a low, ledgy spur of the Moat Range and is one of the best half-day hikes along the Kancamagus Highway. For a modest climb of 950 feet, accomplished at relatively painless grades, you are rewarded with a spectacular clifftop view of the valley and peaks to the south and southwest. The trail passes many interesting boulders, cliffs and rock formations. As a bonus, the Forest Service, which built the trail in 1962, offers an interpretive brochure keyed to numbered stops along the way, available on the WMNF website: https://www.fs.usda.gov/recarea/whitemountain/recreation/hiking/recarea/?recid=77730&actid=50
This was an ideal hike for a gray day when a spring nor'easter was slated to move in late in the afternoon. The trailhead is a parking area off Passaconaway (Dugway) Road, just east of the Albany Covered Bridge.
The loop is usually hiked clockwise. Taking the left fork, you soon climb alongside this rock face.
I made a short foray off-trail at the base of the Sundown Main Cliff to inspect this chaotic boulder jumble.