Pineau De Re has won the Grand National in a nail-biting race that saw 9,000 bets per minute placed with one bookmaker alone.
The 25-1 shot left 10-1 joint-favourite Double Seven trailing in third place, with 14-1 Balthazar King the second over the finish line.
Speaking moments after his victory, jockey Leighton Aspell said it was a "wonderful day".
Aspell, who came out of retirement to ride in the race, told Channel 4: "You know, this is what we do it for.
"I've been watching the National since I was a very young boy, and as much as you enjoy sharing everybody's success, you secretly crave a bit too and it's great to get the chance."
The horse's owner, Dr Richard Newland, said he was delighted with the win, describing Aspell as a "top class jockey".
The world's most famous steeplechase is run over nearly four-and-a-half miles, with this its 167th year.
A number of horses and their riders fell during the race but none were seriously injured, according to Channel 4.
Other years have seen equine fatalities.
Bookmakers William Hill said it took £30 million in bets on the race, with a peak of 9,000 a minute being placed online.
A spokeswoman said the result meant a "relatively small payout" for the bookies.
Paddy Power also said it was breathing a " huge sigh of relief".
A spokesman said: "We were sweating more than Kerry Katona in a maths test towards the end of the race as a win for Double Seven or Balthazar King would have floored us.
"Punters will take some solace in them placing but we're relieved that Pineau De Re held on."
While those who had backed Pineau De Re will be celebrating their winnings tonight, the result will not have been welcomed by one punter in particular.
George Atkinson, who at 103 was believed to be the oldest person to place a bet, was hoping to see his horse come in first after betting on the National for more than seven decades without success.
Mr Atkinson wanted 2011 Cheltenham Gold Cup winner Long Run to be first across the line so he could ''die a happy man''.
He has placed bets religiously on the National each year since the 1940s but has never managed to back a winner, and feared this was his last chance.
Mr Atkinson, from Swaffham, Norfolk, placed his first bet on the race after leaving the Army.
The widowed father of seven, who is a grandfather and great-grandfather, goes to his local branch of William Hill twice a day and even celebrated his 103rd birthday there.
Tens of thousands of people have attended the three days of racing, which is a highlight in the North West's social calendar.
Yesterday's Ladies' Day saw fashionistas out in force at Aintree.
The racecourse has seen the usual display of elaborate hats and fascinators, with one woman even donning headwear made from Mini Cheddars.
The more sensible among them chose flat shoes to negotiate the wet conditions, but others were determined not to let the rain stop them sporting their extravagant heels.
Mark Kennedy, head of science at the World Society for the Protection of Animals, said he was pleased to note no fatalities among the horses in the Grand National.
He said: "It has given us greater confidence in the measures taken to make Aintree safer for horses though, of course, we need to see what happens over the next few years.
"Although the media spotlight was on Aintree this weekend, it's still true that far more horses face danger and death running in jump races across the country and worldwide.
"In the UK alone, for each thousand horses that start a jump race, four will die. At this level of risk fatalities are not freak events; they are predictable.
"WSPA would very much like to work with the global horseracing industry to see how, together, we can protect the welfare of horses."