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.
13. Fun time
This trio seem to be enjoying themselves despite the cold, as they mark the arrival of the New Year at the 2020 Loony Dook. | Ian Georgeson
14. Making a splash
These Loony Dookers made it look fun to plunge into the chilly waters of the Forth at South Queensferry on New Year's Day 2009. Photo: Kenny Smith
15. Date with destiny
This couple decided to ensure a happy New Year was in the frame when they joined the Loony Dook at South Queensferry on January 1, 2014. Photo: Neil Hanna
16. Loony Dook
Men and women in the Firth of Forth at South Queensferry, taking part in the Loony Dook for charity on January 1, 1993. | TSPL Photo: Ian Rutherford