Local scholar and environmentalist Lauren Stevens will guide a hike retracing Henry David Thoreau’s 1844 ascent to the summit of Mount Greylock at 10 a.m. Saturday, July 19. The event is free.

Participants should meet at the Mount Greylock State Reservation, Notch Road gate parking lot, 300 feet up from the intersections of Reservoir and Notch Roads, off Route 2.

The hike is recommended for ages teen to adult. Hikers have options for 8 mile or 4 mile routes; upper sections of the Bellows Pipe Trail are strenuous.

Participants should be prepared for the trail and weather conditions. Sturdy hiking footwear is recommended. Bring a lunch, snack and adequate water.

The event is sponsored by the Department of Conservation and Recreation and Hoosic River Watershed Association. For additional directions and information, call (413) 499-4262.