The Glaubenbielen is the wilder sibling in the family. Reaching 1,611 metres between Sörenberg in the Entlebuch and Giswil in Obwalden, it climbs through open alpine pasture, then drops toward the Sarneraatal in a descent that is steeper and narrower than almost anything you will meet on the more famous passes. This is a road where you want a full tank of patience and a rider who is awake.
On the Sörenberg side the approach is gentle, with big views across rolling grassland and the limestone teeth of the Schrattenfluh away to the west. Then the road lifts to the top, a bare saddle where cloud can descend in seconds, and tips over. The Obwalden side is where the gradient arrives: tight bends, a surface that has seen many winters, and a sense of the valley floor opening far below, with Lungerersee glinting to the south on a clear day and Giswil spread beneath. Use low gears and do not try to be fast. Cows and walkers occupy the verges, and the road is narrow enough that oncoming cars will make you stop.
The pass is closed in winter, normally from late autumn into late spring, depending on snow. If you are early or late in the season, you may find the barrier shut with no particular warning. Locals will tell you it is a matter of weather, not of dates, and they are right.
Giswil, with about three and a half thousand people, is the nearest place to fill the tank on the Obwalden side, and Sarnen is the larger town beyond. In Giswil you can also find a bakery or café, which is welcome after the descent. The Brünig road runs to Lungern and on to Meiringen and the Bernese Oberland, so the valley is a natural link between different routes.
The geology is limestone and flysch, meaning the hills are green and soft in places and savagely steep in others, which is why the road is so twisted. Aim for a dry, clear morning in summer, when the light is soft and the bogs smell of damp earth and wild thyme.