Yakov Sannikov and Matvei Gedenschtrom claimed to have seen it during their 1809–1810 cartographic expedition to the New Siberian Islands. Yakov Sannikov was the first one to report the sighting of a "new land" north of Kotelny Island in 1811 (hence, the name "Sannikov Land").
In 1886, a Baltic German explorer in Russian service, Eduard Toll, reported observing the elusive land during an expedition to the New Siberian Islands. In August 1901, during another expedition led by Toll, The Russian Polar Expedition, Russian Arctic ship Zarya headed across the Laptev Sea, searching for the legendary Sannikov Land (Zemlya Sannikova) but was soon blocked by floating pack ice in the New Siberian Islands. During 1902 the attempts to reach Sannikov Land, deemed to be beyond the De Long Islands, continued while Zarya was trapped in fast ice. Leaving the ship, Russian Arctic explorer Baron Eduard Toll and three companions vanished forever in November 1902 while travelling away from Bennett Island towards the south on loose ice floes.
Despite the intensified search, it was established finally during the first half of the 20th century that the Sannikov Land no longer exists.
Some historians and geographers, judging from other successes of Sannikov and the presence of shallow sand shoals at its mapped location, postulate that Sannikov Land indeed existed, but was destroyed by coastal erosion and became a submerged sand shoal like many other islands, formed either of fossilized ice or of permafrost. This process of disappearing of Arctic islands continues within the New Siberian Islands archipelago. Other historians and geographers hypothesize that Sannikov Land might have been a miraged image, which occur frequently in the Arctic region, of Bennett Island. Another group of scholars regard Sannikov Land as a form of pseudohistory.
Russian geologist and science fiction writer Vladimir Obruchev fictionalized this phantom island in his novel Sannikov Land (1926). In the story, the island provided the last escape for a tribe of Onkilon (in fact, this was one of the older names for Yuit), pushed away from the mainland by other Siberian peoples. The (fictional) Onkilon were thought to be extinct, and were discovered by a small expedition looking for the island and eventually stranded at it.
Obruchev provided a reasonable justification of the possibility of the described things and events. The island turned out to be a crater of a volcano and a warm place, heated by the volcano. It also hosted a tribe of Neanderthals (called "Vampoo") and mammoths. In the end of the story the volcano erupts and destroys the land.
- Mills, W. J., 2003, Exploring polar frontiers: a historical encyclopedia. ABC CLIO Publishers, Oxford, United Kingdom.
- Indiana Progress. 19 Aug 1936.
- White, Calvin S. (16 May 1937). "U.S.S.R. Opens Far North". New York Times. Retrieved 4 November 2011.
- Gavrilov, A.V., N.N. Romanovskii, V.E. Romanovsky, H.-W. Hubberten, and V. E. Tumskoy, 2003, Reconstruction of Ice Complex Remnants on the Eastern Siberian Arctic Shelf. Permafrost and Periglacial Processes. vol. 14, pp. 187–198.
- Grigorov, I.P., 1946, Disappearing islands. Priroda, pp. 58–65 (in Russian)