Mr Cummings was "almost paralysed" in the Italian Dolomites

Andy Cummings, from Brecon, intends to cycle and fell run the 180 miles from Caernarfon Castle to Cardiff Bay in just 18 hours.

His trek will take him along the mountains which form the backbone of Wales - Snowdon, Cadair Idris and Pen y Fan.

Mr Cummings sets off on 5 September.

All the money raised on his journey will go to the charity Spinal Research, which funds work into spinal cord repair.

Mr Cummings, a professional climbing instructor, needed spinal surgery after breaking his back in two separate climbing accidents.

In 1985, he fell while rock climbing in the Peak District, breaking several vertebrae in his lower back.

Eleven years later, he broke two thoracic vertebrae and several ribs, punctured his lung and broke an arm in a fall in the Italian Dolomites.

Andy Cummings will begin his journey at Caernarfon Castle

Both accidents resulted in many months of rehabilitation.

Mr Cummings said: "The climbing accident in the Italian Dolomites almost paralysed me.

"I was amazingly lucky and I've joined Spinal Research's Near Miss Club to help raise funds to improve the quality of life of those who haven't been as fortunate as me.

"On 5 September I'm going to cycle from Caernarfon Castle to Cardiff Bay and run the summits of Snowdon, Cadair Idris and Pen y Fan - the backbone of Wales in a day."

Mr Cummings is still rock climbing and runs a mountaineering company that provides training, assessment and team-building courses for businesses.

Other Near Miss Club members include footballer Dion Dublin, jockey Richard Dunwoody and photographer Lord Lichfield.

Spinal Research said back injuries were typically suffered by young, active people, often in a road accident or fall.

More than 40,000 people in the UK are paralysed as a result of damage to the spinal cord, with around 700 more people suffering paralysis each year.