Ponds, swamps, rolling hills, glacial erratics and rocky outcroppings can be found in the state forest, which features more than 35 miles (56 km) of backwoods roads and trails as well as remnants of 18th-century farming and milling operations.

It was established in 1916, and named for the Massachusetts State Forest Commission's first chairman, Harold Parker, who died that same year.

According to the New England Mountain Bike Association (NEMBA) the single track riding rates; 30% easy, 30% moderate, and 40% difficult with some rocky sections.

and is one of the best mountain bike experiences on the North Shore, and additionally there are over twenty miles of moderately hard cross country trails interweaving throughout.

However detailed maps of Harold Parker are available online for free at the NEMBA web site,[5] and the trails are well marked by DCR.