More than 500 set off from the hall to bike 20, 50 or 100 miles through north Norfolk's glorious countryside today.

First to finish today's flagship 100-mile ride was Jamie Standen. The 50-year-old carpenter from Hunstanton completed the two 50-mile legs route, which took riders as far afield as Gayton and Salthouse, in 5hrs, 21mins and 21secs.

'It was hard but fun,' he said. 'It's a new route this year. I'm local, so I've ridden some of the roads but it was very testing towards the end.

'Bard Hill was a bit of a monster, it's one of the steepest climbs around here.'

Mr Standen arrived at the finish unscathed. Since he began cycling four years ago, he has suffered concussion, a punctured lung, broken pelvis, broken shoulder and broken collar bone falling off his bike.

Ben Hamilton-Watts, manager of the nearby Victoria Hotel at Holkham, completed two 50-mile rides.

'It wasn't too bad, it was a good ride but Norfolk's definitely not flat,' he said.

Zac Wilson from Amersham, Bucks, was the youngest to complete a 50-mile route.

The 10-year-old raised more than £700 in sponsorship for ex-service charity Walking with the Wounded.

His mum Katy said: 'I'm very proud, it's amazing that he's managed to raise as much for the charity.'

Bill Jordan, who owns Pensthorpe Natural Park, near Fakenham, said: 'I did the 50, I went round slowly. I cruised round, I enjoyed it. I'm not very competitive.'

Sky TV cycling presenter Orla Chennaoui, who compered the event, was making her first visit to Norfolk.

'I'm bowled over by how beautiful it is,' she said. 'It's simply stunning.'

Peter Trett, one of the event's organisers, said numbers of riders were 10pc up on last year, with 550 setting off from the hall this morning.

The grounds of the hall have been opened up for camping, with a beer tent, food village and entertainment on offer.

Before the event got under way Holkham's owner the Earl of Leicester, who is a keen cyclist said: 'There'll be a lot of people having fun and some people going through a lot of pain, which will include me because this year I'm a little behind with training and carrying a bit of timber. What we try to do here is put on events which we enjoy.'

Estate director David Horton-Fawkes said the event was aimed at cyclists of all abilities.

'The nice thing is it's not just for lads in Lycra,' he said. 'It's from four upwards, there's families and children, it's not just the blokes heading off.

'We've seen a huge increase in the numbers of cyclists, it's a family thing and the nice thing is it's sociable, you can have a chat while you're cycling along.'

Peter Flett, who runs Hunstanton-based bicycle shop Fatbirds, said booming numbers of cyclists was partly down to a new breed of person known as the MAMIL - middle-aged man in Lycra - who might previously have exercised by playing golf.

But he added: 'It's not something that's age-specific, you can be 70 and ride your bike with someone who's five years old.'

More than 5,000 are expected to attend the event, with the first rides setting off this morning. Those in need of refreshment will not need to ride far to find the beer tent, which spans the finishing line.