Hazel Tyldesley, Trafalgar Square
An exhausted Eddie Izzard is celebrating finishing his 43rd marathon in 51 days - a feat which has raised more than £200,000 for charity.
Mararthon effort: Eddie Izzard gets mobbed by crowds at Trafalgar Square
The celebrity runner was cheered on by 200 people as he completed the amazing feat in the pouring rain in central London.
And after crossing the line he told Sky News: "I'm completely exhausted and I haven't been able to sleep properly.
"Gravity has had a big impact on my body and I don't know what the fall-out will be.
"It will take me a few days to come out of this and then I'll sleep for a week."
The final leg saw him start at Potter's Bar and take in London's Olympic site before heading to the city centre.
It was a challenge that would have pushed even the most hardened athlete - and was made all the more remarkable given Izzard's paltry five weeks of training.
Sport Relief, the sister charity to Comic Relief, love it when sportsmen and women do this stuff but when it's ordinary bozos like you and me they like it even better. Eddie Izzard
His arrival at Trafalgar Square marked the end of a 1,100-mile tour of Britain by foot for Sport Relief.
It saw him battle toenail and ankle problems as he progressed through England, Northern Ireland, Scotland and Wales.
The two-times Emmy winner has run more than 30 miles a day, with just one day off a week.
He said: "When we were hunters we used to hunt this way, so everybody should be able to do this.
On the run
"But at the end I just spear a Twix and have a Diet Coke.
"Sport Relief, the sister charity to Comic Relief, love it when sportsmen and women do this stuff but when it's ordinary bozos like you and me they like it even better."
He also backed a bid for Olympic glory for Britain in the marathon event adding: "If an idiot like me can run 43 marathons just think what a real athlete can do."
Izzard has been accompanied en route by numerous well-wishers and a customised ice-cream van that has played Chariots of Fire to spur him on.
It chimed on the finish line in Trafalgar Square as Izzard finished his final run.
The comedian has re-fuelled not on ice-cream but potatoes, porridge and cake after each run.
Eddie Izzard 
British comedian Eddie Izzard has completed a series of 43 marathons in just 51 days to raise money for Sport Relief, a charity based in the United Kingdom.

The marathons covered a total running distance of 1,100 miles (1,700 kilometers) across the United Kingdom. He ran from London, England, to Cardiff, Wales, to Belfast, Northern Ireland, to Edinburgh, Scotland and back to London again. Izzard carried a flag of each of the four countries depending on which one he was running in.

Eddie is 47 years old and had spent just five weeks training for the event. He crossed the finish line on Tuesday in Trafalgar Square in London during a rainfall. He said to waiting journalists: "I feel dead."

In an interview with BBC News, he commented: "I don't know what the hell I was doing at the end but it must have been way faster than I was doing the rest of the time. So I feel exhausted now, but you know, it's over. Being here is very nice because, when I left here seven-and-a-half weeks ago, there was nothing here, it was just a cold morning and now there's a lot of people here, even in the rain."