The Grimsel Pass (German: Grimselpass) is a mountain pass in Switzerland, crossing the Bernese Alps at an altitude of 2,164 metres (7,100 ft). The pass connects the upper valley of the Rhone, in the canton of Valais, with the Haslital, the upper valley of the river Aar in the canton of Bern. In so doing, and as the Aar is a tributary of the Rhine, the pass crosses the continental divide between the North Sea and the Mediterranean Sea.
The pass is crossed by a paved road, although this is often closed between October and May, due to the high snowfall on the pass. As it is the only direct road pass between the cantons of Bern and Valais across the Bernese Alps, attempts are made to keep the road open as long as possible with snow ploughs. A PostBus Switzerland service crosses the pass several times a day, connecting Meiringen and Oberwald.