We followed these directions exactly, and we had to have some locals get us pointed in the right direction. Ridge Road is 2.3 miles up Cold Spring Road, not 4 miles. Although it's unmarked, it feels obvious, because it runs right on top of an obvious ridge. After you take a right on Ridge Road, you reach Hammonds Rocks in .75 of a mile. We drove the two miles mentioned in the "Getting there", but although we saw an obvious parking area, we didn't see any red blazes. It's still a nice area, grafitti aside.
Your link to Michaux State Forest is broken. It should be: