Some 200 intrepid souls will defy health and safety advice risking broken bones and bruises to chase cheeses down a famous hillside.
Up to 5,000 people will gather on Cooper's Hill, in Brockworth, Gloucestershire, to watch the ancient and dangerous tradition of cheese rolling.
Fearless entrants compete to be first to the bottom of the slope but gradient often sends them bowling head over heels in pursuit of their prize.
The first written evidence of the event dates from 1826, but the tradition was established long before - perhaps as a Pagan harvest ritual.
For the past 21 years the 7-8lb Double Gloucester cheeses have been made by Diana Smart at her family farm in Churcham.
During the war years a wooden cheese was used due to rationing.
The event came under scrutiny in 1997 when 33 people were injured. One spectator lost his balance trying to dodge a bouncing cheese and tumbled 100 feet down the hill. Due to the injury toll the event was cancelled the following year.
The event was also scratched in 2001 when the foot-and-mouth outbreak closed much of the countryside. On both occasions a solitary cheese was rolled to keep the tradition alive.
The event's own website warns: "Some people win, some merely finish and many get injured - even the spectators - with mostly sprains and minor injuries, but also broken bones. To the competitors it seems to be a risk worth taking, as many come back year after year, some from great distances to win the highly prized cheese."
All-time champion is local man Stephen Gyde, from Brockworth, who has won 21 cheeses and is believed to be the oldest winner at 43.
