The border between Norway and Finland is long. It is a land and river border between two tripoints. The western tripoint is Treriksröset on the Swedish border. The eastern tripoint is on Muotkavaara on the Russian border. The border was defined in a treaty from 1751, which also included the Swedish-Norwegian border. In the period 1738-1751 there were field investigations and negotiations on the border, although the Finnish part needed less negotiation. Cairns were erected after that with last one at Nesseby in 1766. A treaty in 1826 with Russia which possessed Finland, defined the easternmost part of the border. Between 1920-1944, the Petsamo area belonged to Finland, so the Finland–Norway border extended along the present Norway–Russia border to the ocean.