An ice disc, also referred to as ice circle, or ice pan, is a naturally occurring phenomenon in slow moving waters in cold regions. It is a thin and circular slab of ice that rotates in the water, widely believed to have been formed by eddy currents.

Ice discs form on the outer bends in a river where the accelerating water creates a force known as 'rotational shear,' which breaks off a chunk of ice and rotates it. As the ice disc rotates, it grinds against surrounding ice, gradually smoothing its edges into a circle.

Ice discs have been observed most frequently in Scandinavia and North America, but they are occasionally recorded as far south as England and Wales.

Ice discs have been seen in clusters and groups of varying different sizes. 

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