As usual, rod, thanks for your great photo essay. I particularly enjoyed the photos of the Reformatory Trail. Last year on the 30+ mile route of the MassBike Summer Ride, we of the Fifty-Plus Forum were directed onto that trail, two of us on road bikes with 25C tires; also the Minuteman National Historic Park trail was part of the route. It was very interesting, but slow-going.
Yesterday was indeed a gorgeous day. Saturday mornings are my only chance for a long distance training ride, and I lost last weekend due to threatening rain. I did a 60 mile loop starting at 5:45 AM, from Norwood on Rte 109 to Millis, Franklin, on to Rte 140 to Milford, where I could not locate the Upper Charles River bike trail, but did pick it up along Rte 85 to Hopkinton. I've only read sherbornpeddler post about it, but IMO it rivals the Minuteman, and is more rural, even as passing through Milford. To paraphrase Horace Greeley,
"Go Southwest young man, go Southwest and ride the Upper Charles River Trail." 
I often ride from Hopkinton to Norwood via Ash, Prentice to Holliston then via Sherborn, Dover and Westwood. Yesterday, I took Highland in Holliston to Winthrop directly back to Medway, a great route. Village Street from Medway through Millis to Medfield is also a very nice street to avoid Rte 109. One of my previously-mentioned “enchanted” roads is Causeway Street off of Forest which intersects Village St, and I usually do a drive-by past a colleague's house to say “Hi” if he’s outside.
Even though it was the Summer solstice, I wore tights and a long-sleeved jersey most of the ride, and my fingers were pretty cold the first hour without fingered gloves.
PS: This is my only picture of the Upper Charles Trail. Sorry it's so fuzzy (taken on a previous ride):
