Notch Road climbs Mount Greylock from the north, and it is rougher, narrower and more atmospheric than the road from the south. It leaves the Hoosac valley near North Adams and Adams and rises steeply through a cleft in the mountain, the notch that gives it its name, with rock outcrops, spruce and a view of the valley falling away behind you. It is often closed by weather or damage, and when open it is a slow, careful ride on a surface that has seen better decades, so check the conditions before you commit.
The valley below has a great deal of history. Adams was the birthplace of Susan B. Anthony in 1820, the champion of women's suffrage, and the house where she was born still stands. North Adams, a former mill town, now has MASS MoCA, an enormous contemporary art museum built in a converted factory, which has transformed the town's prospects. Beneath the nearby mountain runs the Hoosac Tunnel, almost five miles long, bored by hand and dynamite through solid rock in the nineteenth century at the cost of many lives, and the longest railway tunnel in the country when it opened in 1875.
The ride up is a lesson in how quickly the forest changes. At the bottom, the woods are sugar maple, beech and yellow birch, and as you climb the trees shrink and darken into spruce and fir, with moss on the roadside rocks and the smell of resin in the air. The temperature drops, the wind picks up and sometimes the mist rolls over the road. In autumn, the lower slopes blaze red and orange, and in the upper forest the spruce stays dark and still. The corners are tight, often blind, and the road is only wide enough for one vehicle in places, so go slowly and be ready to stop.
Fill up in North Adams or Adams before you go, since there is nothing on the mountain, and there are plenty of diners and cafes in both towns. The Mohawk Trail, Route 2, passes through North Adams and is a scenic road in its own right, with a famous hairpin and views over the valley. The road is closed to vehicles in winter, normally from late autumn until late spring, so the season for riding it is short, but worth waiting for.