Racetrack Playa Explained

Rocks at Racetrack Playa are pushed by ice sheets and wind.

Racetrack Playa is a dry lake in Death Valley National Park.

The playa is 2.8 miles long and 1.3 miles wide.

Rocks weighing up to 320 kilograms slide across the flat surface.

People long thought strong winds pushed rocks on wet mud.

Research shows thin ice sheets melt and push rocks gently.

Ice less than 5 millimeters thick floats and shoves rocks forward.

Rocks move so slowly they can be missed by casual observers.

Time-lapse cameras and GPS tags tracked rocks moving in 2013.

The playa floods shallowly in winter letting ice form at night.

Rocks can move simultaneously over 60 meters before stopping.

The Grandstand is a 73-foot high rock island in the playa.

Racetrack Playa’s surface cracks into small hexagonal mud polygons.

Visitors need high clearance vehicles and no mobile reception nearby.

Rocks at Racetrack Playa move pushed by ice sheets and wind.