Chestnut Ridge begins at Shaw Gap on the north side of Iron Mountain trail. After a half mile of gentle downhill and then a short climb, the plunge gets steep and follows a descending ridge. This trail is incised in places with rocks (and usually leaves) in the ditch. Sometimes referred to locally as "Mill Creek," it is also known to have frequent blowdowns, so be prepared to get over logs that have fallen in the trail.
At about 1.5 mi, near the bottom, there is a hard RIGHT that arrives just after the steep section in a wet, rooty area. Take a right here and you'll be at the bottom quickly.