It connects the southern part of the canton of Solothurn via Mümliswil-Ramiswil (south of the pass) and Beinwil, Solothurn (northern side) with the so-called Schwarzbubenland (officially Amtei Dorneck-Thierstein, consisting of the canton of Solothurn districts Thierstein and Dorneck) north of the Passwang mountain chain, and ultimately with the Laufen District in the canton of Basel-Landschaft.
