Biking Milford MA
The trail head is off 495S the 109 exit of Milford - take a right, right at the light, right at the light, and then a right into the American Athletic Club to park. Bike left out of the parking lot, and right up the gravel path to the power lines.
You could just ride the power line trails if you like gravel, but if you go 100 yards along the lines, and then go right into the woods, there's a trail about 100 feet into the woods. The trail goes for miles and miles, forking, over rocks, through streams, you name it. There are a lot of technical spots, and also overhanging trees and jutting bushes in many areas. The trails are not really "maintained" except by bikers' bodies.
Try to keep aware of where you are. We passed many lost bikers groups and in fact barely made it out ourselves before sundown. There are no trail names or maps, as far as I know. Perhaps this should be a new job of mine ...
As a side note, this set of trails is called "Vietnam" by many bikers :) Don't expect an easy ride!!
"Mountain Biking Near Boston"
an excellent reference with maps!
Biking in New England