The story of the WI ladies who decided to strip off for a risqué charity calendar is being told in a new exhibition.
Twenty Years Of The Calendar Girls tells the story of the Women's Institute in Rylstone, North Yorkshire.
The original calendar featured 11 members, who covered their modesty with pianos, flowers, teapots, song sheets and sewing.
Since its release it has raised more than £5m for the Bloodwise charity.
The calendar was the brainchild of Tricia Stewart, who was portrayed by Helen Mirren in the 2003 blockbuster of the same name.
It was intended to be an alternative to the usual fare of rolling hills and sheep, she said.
What started out as a joke became a reality after fellow WI member Angela Baker lost her husband John to cancer on 22 July 1998.
"After John was diagnosed, the idea of a calendar returned. We told him about it and he thought it was very funny but said we would never do it," she said.
The women worried the calendar would not sell but within weeks of launching it was a huge success and went on to spawn the film, stage play and musical.
Christine Clancy, who was Miss September, said: "We've had a great deal of fun but we never lose sight of the reason why we started it all.
"It was all in memory of John Baker to raise money for Bloodwise to hopefully find a cure for these dreadful blood cancers."
The WI's calendar sparked a worldwide craze, inspiring others from all walks of life to bare their bums for good causes.
Men have also been persuaded to pose for a number of calendars, including a group of husbands and boyfriends who "volunteered" to strip at the behest of their local WI.
It was a sell-out success.
Perhaps the most prolific producers of nude calendars are university sports societies, who have proved particularly eager to get their kits off.
The (rear) end results often receive press coverage, and student newspaper The Tab runs a yearly round-up of its favourite offerings.
However, the calendars are not without controversy.
The women of the University of Warwick's Rowing Society were banned from Facebook after their calendar was flagged up as pornography, while a Derbyshire tennis club also fell foul of the internet giant's strict rules on nudity.
The exhibition celebrating the women's achievement runs until 30 September at the Dales Countryside Museum in Hawes.