More than 200 people are expected to compete in the World Stone Skimming Championships being held on the Scottish island of Easdale on Sunday.
The event is open to anyone, with heats in four categories: adults over 16, over 60s, girls and boys aged 10 to 15 and the under-10s.
Stones must be no more than 3in, formed of Easdale slate and bounce no less than three times within the boundary.
Skims are judged on the distance thrown rather than the number of bounces.
The World Stone Skimming Championships were started up in 1983 by Albert Baker.
It was not held again until 1997, when it was resurrected by the Easdale Island Trust as a fundraising event.