Brimfield State Forest Mill Brook Circuit

Mill Brook carved its way through Brimfield’s granite ledges long before the CCC boys built these forest roads in the 1930s. The circuit follows old logging tracks and fire roads through dense mixed forest, crossing Mill Brook at three points where colonial-era mill foundations still poke through the undergrowth. Rocky climbs test traction on the north loop, while the southern section drops into boggy lowlands that turn into proper mud wallows during spring snowmelt and autumn rains.

Difficult rating comes from technical rock gardens and water crossings that require 4WD with skid plates and recovery points. Avoid during mud season (March-April) unless you enjoy winching. Summer and fall offer the best conditions, though black flies can be biblical in June. No camping permitted, but nearby private campgrounds serve as base camps. This gives you a solid day of technical driving just 90 minutes from Boston, plus the satisfaction of following routes that Connecticut River Valley loggers used when these hills fed the Industrial Revolution.