Two men who have a combined age of 122 have made a pledge to cycle from John O'Groats to Land's End this summer.

To make the challenge even harder, Trevor Williams, 56, and his brother Bryan, who is 10 years his senior, have decided to take a unique route which goes through Scotland, Ireland, Wales and finally England.

The brothers will cycle more than 1,100 miles with 50,000 feet (15,240 metres) of climbing over three weeks.

They have pledged to undertake the challenge through Active Norfolk's Pledge 2012 scheme.

The initiative calls on the people of Norfolk to make a fitness or health commitment in the run-up to the Olympic and Paralympic Games.

Trevor, who is in the process of moving from Peterborough to Aylmerton, near Cromer, said: 'This is a big challenge. It will take us about three weeks. We will carry everything we need ourselves and stay in bed and breakfasts along the way.

'We're certainly taking the scenic route. We are travelling through Scotland's central Highlands and down the west coast.

'Then it will be a ferry to Ireland and along the east coast, through the Wicklow mountains, a ferry to Fishguard, along the south coast of Wales, over the Severn bridge and on to Land's End.'

The pair will set off on their epic ride on April 28 and are raising money for Help for Heroes, Sense, Get Connected and A National Voice.

It will be the first time the brothers have ridden together as Bryan, a retired professor, lives in Scotland.

Trevor, who has retired from the Ministry of Justice and is moving to Norfolk due to his love of birdwatching, said most of his training has been done on an indoor trainer over the winter.

The married father-of-five, who has four grandchildren, said: 'I've never done anything like this before. Completing it is the number one objective.

'The hills will be the toughest part and Scotland can be cold and windy at this time of year but we're taking our time with it and are looking forward to seeing four countries in all their glory.'

Trevor has joined a long list of people making a pledge through Pledge 2012. The scheme is run in partnership with Norfolk County Council and NHS Norfolk and is supported by the Eastern Daily Press and BBC Radio Norfolk.

Vicki Hall, from Active Norfolk, added: 'I can confidently say this is the biggest pledge we've had in the campaign so far. These two are an inspiration and I hope their fantastic trip will encourage people to get on their bikes – even for just a short ride round the block.'

To follow Trevor and Bryan's progress, follow them on Twitter @trevorontour or go to www.trevorontour.me.

To sponsor them, go to www.justgiving.com/teams/justice.

To make a pledge, go to www.pledge2012.com.

kate.scotter@archant.co.uk