About 1,000 people are due to take to the freezing waters of the Forth Estuary in the 26th successive Loony Dook event.
It is being preceded by the grand parade of Loonies near the Forth Bridge.
The event is expected to raise thousands of pounds for charities.
About 50 people are also taking part in a swim at the East Beach in Dunbar to raise money for Chest, Heart and Stroke Scotland.
http://www.bbc.co.uk/news/uk-scotland-edinburgh-east-fife-16377795
bloody loonies