More than 4,000 young people came from all parts of Dorset for a service at Maumbury Rings.
They met at Charles Street car park and paraded through the town centre before gathering at the Roman amphitheatre.
Pam Marsh, Dorchester assistant district commissioner who was one of the main organisers, said: “We always have a St George’s parade in Dorchester and this year I thought it would be a good idea to hold it here for the whole county as it’s the centenary.
“Maumbury Rings is just about the only place big enough for us all so I’m
glad we’ve been lucky with the weather.”
The event, which marked 100 years since Robert Baden-
Dorchester town clerk Dennis Holmes said the town council, which manages Maumbury Rings, had been pleased to help with the event.
He said: “This is the county town and it seemed right with the centenary to have the gathering here in Dorchester.
“There’s never been anything like it here at Maumbury Rings and I hope it gives everyone a really good experience that they’ll never forget. It’s also a credit to all the adults who support scouting and make it happen in Dorset.”
Special trains were laid on and coaches used to bring a total of 4,300 young people to the county town.
Among the guests and civic dignitaries attending were mayors from across Dorset.