The Arctic Ocean Hydrographic Expedition (GESLO) (1910–1915) was a scientific expedition organized by Russia for the purpose of the development of the Northern Sea Route.
This expedition accomplished its goal of exploring the uncharted areas of the continental side of the Northern Sea Route in what was seen as the culmination of the Great Northern Expedition, an ambitious enterprise initially conceived by emperor Peter I the Great to map the whole of the northern coast of Russia to the east.