The World Conker Championships have been taking place in the village of Southwick, near Peterborough.
Hundreds enjoyed what was described as a bit of "great old British fun" - but organisers say the competition isn't without its hazards.
St John Burkett, 57, who has been arranging and participating in the event for more than 20 years, said poor technique can often lead to aching limbs. His tip for avoiding injury: strike at an angle.
Burkett, an educational adviser from Barnack, Peterborough, said the day offered championship attendees a chance to relax and make the most of the autumnal sunshine.
Despite a blustery start to October and some less-than-ripe conkers on the ground, former soldier Ray Pearson, 81, managed a first-round win alongside his Chelsea Pensioner chums.
He said: "Like all battles in all wars you always want to win.
"But like I always say to my grandchildren: no-one can win if you don't play."
The contest features men's, women's and group competitions.