I parked in the village of Milford and biked down rt 13 south to the town garage where the trail head is. Mile ~1.2 near where the trail leaves the RR grade and passes through private property was the location of a series of switch back rail tracks that allowed a train to traverse up that hill, probably in support of the rock quarry that was at the top. (This can be seen on old Dept of the Interior US Geological maps of Milford.) I then rode the rail trail down into Brookline where other trails become available. For the return route, I found a trail that eventually took me back to Osgood Road in Milford. I passed some interesting spots, like the remains of other granite quarries. There are other trails I need to go back to explore. If you get on the trails that are off of the Rail Trail, there are some pretty steep and rocky grades to deal with. On the rail trail itself, there are lots of tree roots. I've done this ride on both a hard tail and full suspension mountain bikes. It's a lot more enjoyable with a full suspension bike.