One motorcycle, 2,500 miles and little more than two weeks.

This is the challenge ex-serviceman Keith Varney has accepted in aid of the Bridge for Heroes charity.

On June 25, Mr Varney, of King's Lynn, will join nine other men at the start line at the Lollipop Diner near Diss, where they hope to finish between 15 and 18 days later.

The keen motorcyclists - all raising money for different charities - will travel approximately 2,500 miles, first riding north up the eastern side of the country to John O'Groats and across the Scottish Highlands.

They will then travel down through the Lake District, Wales and the Cotswolds and all the way to Lands End.

The final stretch will take the riders - who have aptly-named the undertaking the 'Steel Butts' challenge - along the southern counties to Margate. The last day's ride is a gruelling 150 miles from Shatterling near Canterbury back to the diner.

Mr Varney, who was in the catering corps for 12 years, said his friend wanted to celebrate his 50th birthday by riding the Route 66 in America but, when this trip was cancelled, they created their own route here in Britain.

'It's all about the freedom, you can do what you want, when you want. It's the camaraderie of the biking world itself. If you are broken down on the side of the road and two bikes come along, they will stop and assist you,' he said.

The fundraiser, who said he had 'ridden on and off' all his life, will sleep under a basha - a 10ft piece of Gortex material which will be pegged into the ground.

Bridge for Heroes, based in Lynn, supports the armed forces community, veterans and their families.

Mr Varney, who completed a sky-dive for the charity earlier this month, said: 'I know what PTSD is because I have suffered it in the past. I know these guys do a lot for servicemen and ex-servicemen who are suffering with PTSD. I know they are always looking for donations. I can bring together my love of biking and my voluntary work.'

To sponsor Mr Varney go to www.justgiving.com/steelbutts. Are you taking on a challenge for charity? Email sophie.biddle@archant.co.uk