The first fully documented use of the Grimsel Pass dates back to the 14th century, although it has been suggested that the pass was used in Roman times and also, in 1211, by troops of Berthold V, Duke of Zähringen. In 1397, the Landschaften of Pomat, Goms and Hasli, and the cities of Interlaken, Thun and Bern, signed an agreement in which it was agreed to provide for free and secure trade by the mule track over the Grimsel. The Grimsel Pass formed, along with the Nufenen and Gries passes, a regional trade route between the Haslital and Domodossola and the Lombardy plain. Cheese and cattle were sent south, whilst wine, rice, corn and olive oil came north. This trade continued until the opening of the Gotthard railway in 1882. The track over the pass was not upgraded to a paved road until 1894. Between the 1920s and the 1950s, several hydro-electric power plants were constructed in the area around the pass by Kraftwerke Oberhasli, which resulted in the expansion and diversion of the pass road. The KWO now promotes the pass and surrounding area as a visitor attraction, as part of its Grimselwelt tourism brand.
Geography
The Grimsel Pass connects the cantons of Bern, to the north, and Valais, to the south, with the summit of the pass lying on the cantonal boundary. The northern slopes of the pass are in the Bernese municipality of Guttannen, whilst the southern slopes are within the Valais municipality of Obergoms. The approach to the Grimsel Pass from the north commences in the small town of Meiringen, from where access is possible down the Aare valley to Interlaken and Bern, and across the Brünig Pass to Obwalden and Lucerne. The approach passes the village of Innertkirchen, where the road to the Susten Pass diverges, and continues alongside the Aare to Guttannen. Beyond Guttannen, and still following the river, the road passes a pair of short tunnels to Handegg, where the lower station of the Gelmerbahn funicular, the steepest in Switzerland, is located. After Handegg the road climbs through several hairpin bends and an tunnel to the Räterichsbodensee reservoir. A further climb brings the road to the Grimselsee reservoir and the Grimsel Hospice. Here the final climb to the summit commences, with several more sweeping hairpin bends. At the summit are several hotels and an extensive area of parking. Here the road runs alongside the Totesee, a natural lake that has been enlarged into a reservoir. To the west of the pass and lake is the peak of the Sidelhorn, whilst to the east is the mountain range Schafberg. From the Totesee the pass road descends steeply through more hairpin bends to Gletsch in the most upper valley of the Rhône, the Obergoms. Here connection is made with the Furka Pass, connecting with the canton of Uri, as well as the lower level route down the Rhône valley towards Brig through the Goms. A short distance down the Goms are Oberwald and Ulrichen. At the latter, a junction is made with Nufenen Pass, into the canton of Ticino, and the Gries Pass, to Domodossola in Italy.
Climate
Due to the high altitude of the pass, and its continental location, the climate is cool or cold all year round, and receives a fair amount of precipitation year-round. Snow usually falls from late September until late June, although during cool spells, it can snow at the height of summer. Most years, permanent snow fields remain at the pass, due to the temperature rarely rising above 15 °C. This area has a long winter season, with little precipitation mostly in the form of snow, and low humidity. The Köppen climate classification classifies the climate here as subarctic, and abbreviates this as Dfc.