An adventurer who made history by swimming the length of Britain has said it is a dream come true to cross the finishing line.

Sean Conway, 32, left Cornwall on June 30 and swam along the west coast to the most northerly point of the mainland, from Land's End to John O'Groats.

He braved cold waters, jellyfish stings and even sea sickness to complete the estimated 900-mile route.

He finished the final mile today, making him the first person to swim the length of the UK.

Speaking in John O'Groats shortly after exiting the water, Mr Conway said that it feels "incredible" to be on dry land.

"I've been dreaming of swimming into the John O'Groats harbour for a very long time," he said.

"I had a screengrab of the harbour on my laptop and I've been looking at it for ages. To finally be here and be warm and dry and on land is a good feeling.

"I've been dreaming about finishing for a long time. Just a week ago I thought I might have to give up and finish the attempt next summer, with the bad weather, but we had a few good weather windows and I was able to finish it."

He initially planned to complete the swim in two months but bad weather and injuries took their toll, increasing the time it took. He managed around 10 miles a day and slept on a yacht or in accommodation on the shore.

Mr Conway, who was born in Zimbabwe but now lives in Cheltenham, Gloucestershire, said he undertook the challenge because people doubted that it could be done.

The swimmer, sponsored by swimwear brand Speedo, said: "People told me I was going to die and it wasn't possible and it's never been done before. I thought, 'Hang on, surely it's do-able? I'm going to prove people wrong'.

"It's nice to finish something that I knew was possible, even though it was a lot harder than I thought it would be."

He said swimming in phosphorescence in the Irish Sea was the best part of the journey and "potentially one of the best moments of my entire life".

But other aspects of the endurance test proved hard to bear.

"Dealing with the cold and the big waves and trying to get the support boats to safety after each session was quite hard. The water was just going to get colder and colder the further I got into winter. I was losing weight as well, so it was doubly cold. That was really tough to deal with.

"I get sea sick as well which wasn't fun."

He also suffered jellyfish stings on his face, something which prompted him to grow a "ridiculous beard" for protection.

The support of people on social networking sites, and those who cheered him on from dry land, kept him going, he said.

He was joined in John O'Groats by friends and family and even some supporters who waved him off at Land's End.

Mr Conway has so far raised around £6,000 for the War Child charity in the process. People who wish to donate to the cause can still do so online.

The adventurer appeared undeterred by the harsh experience and suggested a further endurance challenge is just around the corner.

"I've done a long cycle, I've done a long swim, so I think I should definitely do a long run. I think that's next. But in the meantime I need to write the book and talk about this experience and hopefully thaw out a bit."

Mr Conway is described as "self-confessed nutter'' on his own website.

He started his endurance adventures with a mile swim across a lake at the age of 10 and competed in endurance kayak marathons when he was a teenager.

He has also climbed Kilimanjaro dressed as a penguin and cycled 16,000 miles through six continents in 116 days, much of it with a fractured spine, according to seanconway.com.