The Oberalp is the pass that links Andermatt in the Urseren valley with Disentis in the Surselva, and at 2,044 metres it is the road's high point and a historic watershed. Just above the summit, the little Lake Toma is regarded as the source of the Rhine, the river that eventually runs through Germany and the Netherlands and into the North Sea. A short walk up from the car park gets you to the lakeshore, where a plaque marks the spot.
The riding is smooth and enjoyable, with the road swinging up from Andermatt in wide hairpins, then crossing a high plateau where the wind can be fierce. The red trains of the Matterhorn Gotthard Railway run alongside the road for much of the way, part of the Glacier Express line, and the sight of a train snaking through snow sheds or across a stone bridge is a fine bonus. On the Graubünden side the road drops towards Sedrun and Disentis in graceful sweeps, with views of the Vorderrhein valley opening below.
The area is an important one for the history of the Alps. Andermatt was a garrison town with a military past, and the fortifications still hide in the mountain. The valley was settled by the Walser people and others in the Middle Ages, and the Oberalp route was in use long before the road was paved. The weather can change fast, and a cheerful morning can turn into rain and low cloud by lunchtime, with snow possible even in summer at this altitude.
The road closes in winter, and the railway takes over, running all year, so the pass is usually shut from late autumn until late spring. In early summer there can still be walls of snow beside the road. Late summer, when the air is clear and the days are still long, is a particularly good time.