Tukulan

Tukulans are sand dunes shaped by wind action in the Central Yakutian Lowland of Yakutia, in the Russian Federation, appearing as isolated dunes or broad sand-covered stretches across the surrounding taiga plains, mainly along the Lena River valley and the lower Vilyuy River. The largest recorded tukulan runs nearly 40 kilometers in length near the Linde River. Like other dune fields, tukulans build up as aeolian, wind-driven processes gradually move and reshape sand into their characteristic ridges.