In the summer of 1807, Göran Wahlenberg, a Swedish naturalist and a professor at Uppsala University, carried out observations and surveys in Salten and on the Sulitjelma massif. Wahlenberg published his report in 1808, making the Sulitjelma massif the best-described mountainous area in Scandinavia. Carl Linnaeus's journey to Salten more or less followed Wahlenberg's earlier route, via Kvikkjokk to Virihaure and then to the north of today's Rago National Park and down to Leir Fjord in Sørfold. From the Sami, Wahlberg had heard that the easiest way to Sulitjelma passed through Vatenbygda above the lakes Nedrevatnet (Lower Lake) and Øvrevatnet (Upper Lake), and further through the narrow Langvann Valley to its end at Mount Ráhpes (Pite Sami: Ráhpesvarre), also known as Rupsi ().: