The Sailing Stones
On a dry lake bed in Death Valley, heavy rocks leave long trails behind them, but nobody had ever seen one move.
What was reported
Racetrack Playa is a flat, dry lake bed high in Death Valley. Scattered across it are rocks, some weighing hundreds of kilograms, each at the end of a long, shallow trail carved into the mud. Some trails run straight; others curve or zigzag.
For decades, nobody saw a rock move. Explanations ranged from strong winds to magnetism to pranksters.
Explanations offered
In 2013 and 2014, a team of scientists fitted rocks with GPS trackers and filmed them moving. After rain, a thin layer of ice forms on the shallow water. When it breaks up on a sunny day, light winds push the ice sheets, which push the rocks a few metres a minute.
- When
- Seen since the early 1900s; solved in 2014
- Where
- Racetrack Playa, Death Valley, California, USA
- Witnesses
- Visitors and scientists
- Status
- Explained
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.