The high part of the Kancamagus is the part that makes you glad you came. Near the middle of the route, the road crests the Kancamagus Pass, at around 870 metres, the highest point on the highway, and the Swift River begins its run toward the east. The road here is a long climb and a long descent, with fine views over rolling forested ridges that go on forever, a big, quiet landscape of the sort that New England does particularly well.
The east side of the pass is lovely. Corners come in friendly sequences, the road follows the Swift River, and there are waterfalls, gorges and swimming holes a short walk from the road: Sabbaday Falls, a pretty cascade down a rocky flume reached by an easy trail, and Rocky Gorge, where the river is squeezed between granite walls. The Russell-Colbath House, a restored farmhouse from the nineteenth century, is a reminder of the people who once farmed in this valley, long before the national forest was created. The tarmac is smooth, the bends are well-banked, and the road is a joy at moderate pace.
Weather changes quickly at the pass. Mist and low cloud often drift over the summit in the morning, and snow can arrive early in October and linger until April, closing parts of the road briefly during storms. Summer is the busiest season, and the middle of a fall weekend is the busiest of all, with slow convoys, crowded pull-offs and limited parking. If you want the road to yourself, go early on a weekday, and take warm gloves: at the pass the temperature can be ten degrees lower than in the valley.
The nearest stations are in Lincoln, to the west, and in Conway, to the east, and both are far enough to matter if you have a small tank. Bring water, a rain jacket, and a camera. The forest service charges fees at many of the trailheads and picnic areas, and moose cross the road at dawn and dusk. Slow down, enjoy the long view, and be grateful for a road that is mostly about where you are.