Kirkgate Market is hoping to break the world record for the most people wearing flat caps at a single event.
They have planned the bid to celebrate Yorkshire Day on August 1.
Hats off to the great Yorkshire flat cap
Anyone is invited to turn up to Leeds' historic indoor market wearing a traditional Yorkshire flat cap.
Flat caps made on Leeds mill museum's looms win major award
There will be themed food and drink on offer, including Yorkshire pudding wraps, and the finals of the regional youth market competition will be taking place on the same day.
More information will be released nearer the time on Kirkgate Market's social media pages.