INTREPID climber Graham Blackmun from Christchurch was on top of the world - literally and emotionally - when he joined the exclusive band of British mountaineers who have conquered the world's highest peak.

The computer analyst from Purewell was among a dozen climbers and Sherpa guides who successfully scaled the north ridge of Everest to reach the summit more than 29,000 feet (8,848 metres) above sea level.

Since the first recorded conquest of Everest in 1953 only around 150 British climbers have achieved the feat including Dorset adventurer Bear Grylls.

After reaching 7,000 feet the team relied on bottled oxygen, the extra weight of the cylinders outweighed by the need to breathe where the air is too thin to support a rescue by helicopter.

While several of his band fell by the wayside Graham, 50, made it to the very top despite suffering from fatigue and minor frostbite.

"I was surprised to get there, to be honest," he said. "Getting to the summit was an emotional moment. It is definitely quite a feeling to be at the top of the world. It was just such a beautiful day and, by Everest standards, quite warm."

After taking six days to make the final assault on the rocky, icy and at times sheer face of the mountain's northern ridge Graham spent just 10 minutes at the summit before embarking on the equally difficult descent.

His ascent of Everest was the highpoint of a three-month expedition to the Tibetan side of the Himalayas and the pinnacle of Graham's climbing career which has previously seen him scale the nearby Cho Oyo, sixth highest mountain in the world, and North America's highest point, Mt McKinley in Alaska.

"I have always loved mountains and climbing and thought I would have a shot at Everest before I got too old," said Graham.

He was sponsored by his employers TAC and colleagues at the Leicester-based company and hopes to have raised more than £1,500 for the Macmillan cancer trust at Christchurch hospital.