Unlike ordinary sand dunes, the Shifting Sands consist of highly magnetic volcanic ash from the active Oldoinyo Lengai volcano. Researchers believe the dune formed more than 3,000 years ago following a volcanic eruption. The magnetic properties of the ash bind the particles together, allowing the dune to retain its distinctive crescent shape as it moves slowly across the plains instead of being scattered by the wind.
The dune stretches approximately 100 meters along its curved length and rises between 5 and 9 meters high, depending on seasonal conditions and the measurement point. It is composed of fine, iron-rich black volcanic ash, giving it a striking dark color that contrasts sharply with the surrounding grasslands, scattered acacia trees, and open plains.
Driven by strong winds, the dune migrates westward at an average rate of 15 to 29 meters per year, continuously reshaping its surface with beautiful grooves and ripple patterns. Over the centuries, it has occasionally changed both its shape and direction, initially moving southwest before gradually turning westward.
What makes the Shifting Sands truly remarkable is that they exist as a single, isolated dune. Most dunes of this type occur in extensive dune fields, making this solitary formation exceptionally rare. The site is easily accessible via trails descending from the Olduvai Gorge toward the eastern Serengeti grasslands, offering visitors a chance to witness one of Africa's most fascinating geological phenomena.