The Queen was mobbed this afternoon when hundreds of royal fans cheered as she toured a rain-swept event staged in her honour.
Several thousand people gathered for the one-off "Diamonds in the Park" event outside Crickhowell, today.
The showcase for traditional country pursuits and skills took place in fields on the sprawling Glanusk estate in Powys, Mid Wales.
Everything from fishing techniques to manual sheep-shearing was on show, but as the heavens opened many felt the Queen would be forced to abandon a planned walkabout.
She arrived with her husband in matching royal Range Rovers, and the crowd cheered when she decided to brave the teeming rain and the mud bath the event field had become.
More than 4,000 children from across Powys were invited to today's event and almost all of them cheered when the Queen began a walking tour.
Security officers were quick to protect her as a huge throng immediately pressed round the Queen.
With cries of "there she is" hundreds carrying cameras enthusiastically ran towards the Queen as she watched a fishing demonstration overlooking the River Usk.
She then moved on to a demonstration of manual sheep shearing and watched another stand where the fleece was being spun
Despite being almost the only person present not wearing boots, the Queen walked through mud and puddles, smiling at the flag-waving crowd and stopping occasionally to shake hands.
As the rain fell with increasing force she was handed a transparent plastic umbrella and carried on with the tour.
"I think she is absolutely marvellous for her age. She had a beaming smile and was obviously happy to be here," said Ann Bickerton, 73, a member of the Brecon Spinners who demonstrated wool spinning for the Queen.
"She was very interested in the shearing and then she saw the spinning and the knitting going on next to me. It was like looking at a production line.
"She showed a lot of interest in everything and absolutely beamed at you when she came over. She has such a beautiful smile.
As the unexpected tour continued the Queen met emergency service personnel from across the county.
Among them were a mountain rescue group, cadet volunteers with Dyfed Powys Police, dog handlers and their animals and members of a police marine unit.
Children screamed in delight when the Queen came into view, many taking her picture with their camera phones.
She also visited tented stands where ponies, goats, chickens and rabbits were on display.
The show today was put together to appeal to the Queen's long-standing interest in outdoor life and the countryside.
The Queen concluded her tour of the Diamonds in the Park celebration by meeting members of the Armed forces.
Afterwards she was rejoined by her husband and both were driven to a field where a helicopter was waiting to take them back to London.
As the royal couple left the crowd broke into spontaneous applause and gave them three cheers.