Great Blue Hill is the highest summit in the Blue Hills Reservation, lying just a couple miles south of the Boston city limits. At 635 feet, Great Blue is no giant, but it's big enough to make it the highest point on the entire Eastern Seaboard within 10 miles of the shore, not counting Maine. I know, that's a lot of qualifiers --but when you're inching your way up its steep slopes, it feels like something mighty special indeed.
Great Blue is well known among area cyclists as a gem of a climb, with gradients that send your cycling computer into nice little hysterics. Mine was recording +20% grades, which I think is a bit exaggerated. The general consensus gives it a 9-10% average grade, with some maximums between 16-19% -- more than enough to get your legs burning, especially as the trees becoming increasingly windswept near the granite-encrusted summit.
The "Summit Road" that runs from its base right up to the top is closed to all cars, except those traveling on official business to the historic and still-active weather station at the summit.
...and soon afterwards you're on the top of Great Blue Hill.
Then it's time to head back down for a thrilling descent.