The annual event is said to date back to 1987 when three locals jokingly suggested a January 1 dip in the chilly waters of the Forth as a cure for Hogmanay hangovers.
From small beginnings, the event grew in size and popularity during the 1990s, was added to the official Edinburgh Hogmanay publicity material and even broadcast live by the BBC at the millennium.
The event usually attracts around 1,000 people, many in fancy dress, to raise money for charity. And some people come from abroad to take part in the swim.
The official Loony Dook was cancelled for new year 2021 and 2022 because of Covid and the 2023 event was not included in the official Hogmanay programme, but dedicated Dookers went ahead anyway.
Scroll through these pictures to enjoy Loony Dooks past – without having to take the plunge.
9. Plunging in
This Loony Dooker seems to be enjoying making a splash on January 1, 2017 Photo: James Chapelard / SWNS
10. Breaking free
Swimmers brave the waters of South Queensferry for an unofficial 'Loony Dook' on New Year's Day 2023. | National World
11. An ice day for a dip
It looks like these Loony Dookers found the water a little chilly when they went for their dip at South Queensferry on New Year's Day in 2010. Photo: Ian Rutherford
12. Brave souls take a dip
Hundreds of brave souls took to the cold waters of the Forth for the annual dip at South Queensferry on January 1, 2017. Photo: James Chapelard / SWNS