The route is 387.6 kilometres (240.8 mi) long and runs east–west through Viken and Vestland counties over the vast Hardangervidda plateau.

The road begins at the European route E16 highway just south of Heradsbygda in Ringerike municipality and runs through the Sogna river valley to the village of Sokna (this part is called the Soknedalsveien).

It then continues further on to Hamremoen and up along the east side of the lake Krøderen to Gulsvik, where it crosses the river and then follows the Hallingdalen valley through Flå, Nesbyen, Gol, Torpo, Ål, Hol, and Geilo (this part is called the Hallingdalsveien).

The portion of the road from Haugestøl to Eidfjord (over the Hardangervidda plateau) is designated a National Tourist Route.

There are also some unofficial proposals to build a 15-kilometre (9.3 mi) long tunnel under the Hardangervidda plateau,[2] because this stretch is often closed due to snow storms in the winter.