The countdown for the next Winter Olympic games is on – as a giant clock was unveiled in South Korea.

A ceremony in Seoul, hosted by the official timekeeper Omega, marked exactly one year until the Games in Pyeongchang.

Four sports will debut in 2018 – snowboarding big air, mass start speed skating, curling mixed doubles and the alpine skiing team event.

The games will be held from February 9 to 25 next year.