Hundreds of giant, naturally-formed snowballs have appeared on the beach near a remote Russian village of Nyda in the Arctic Circle.

According to the BBC, the icy boulders covered the 11-mile stretch of coast and vary from the size a tennis-ball to 3-ft across— which is around the size of a large exercise ball. The sculptural orbs are created during a rare environmental process where fragments of ice in the near-frozen sea grow into large spherical balls after being continuously rolled near the shore shore.

Villagers say they have never seen anything like it. “Even old-timers say they see this phenomenon for the first time,” Valery Akulov, from Nyda’s village administration, told the Siberian Times.

A similar phenomenon was witnessed in 2013 at Lake Michigan, when dozens of beach-ball sized balls populated the shoreline.

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