AFTER completing the first three legs of his world-first challenge, Richard Parks is set to be joined by some Great Britons on the remaining challenges.

Former Newport Gwent Dragon and Wales rugby international Parks set out in December to climb the highest mountain on each of the world's seven continents and venture to the North and South Pole.

The aim was to complete this in seven months, while he hopes to raise £1 million for Marie Curie Cancer.

Parks reached the summit of Mount Aconcagua last week, South America's highest peak after making it to the South pole and conquering Mount Vinson, Antarctica’s highest mountain.

He is now preparing to climb Africa's highest peak, Mount Kilimanjaro in Tanzania, with Marie Curie nurse, Janet Stuart, before taking on Carstenz Pyramid, Indonesia.

But, then come the back-to-back legs which will make or break the challenge, where Parks will travel the last degree to the North Pole and climb Mount Everest, the world's highest mountain. He will be joined on these legs by two-time Olympic gold medallist rower Steve Williams.

Explorer Sir Ranulph Fiennes - the inspiration behind Parks' odyssey - will then join him for the final leg, Europe's highest peak, Mount Elbrus in Russia.

You can follow Parks at 737challenge.com.