Eliud Kipchoge has become the first runner to finish a marathon in under two hours.
The 34-year-old Kenyan completed the course in Vienna, in an incredible one hour, 59 minutes and 40 seconds.
Kipchoge was racing alone but assisted by 41 pacemakers, including former Olympic and world record holders, in his attempt to achieve the milestone.
Eliud Kipchoge crosses the line to become the first athlete to run a sub-two hour marathon
The 34-year-old Kenyan celebrates with his arms stretched after smashing the world record
The Kenyan runner points to his record as he clutches his country’s national flag
The time will not be an official world record but is nonetheless a historic moment in distance running.
The INEOS 1:59 Challenge was Kipchoge’s second shot at the record after missing out by 25 seconds in his first attempt in Monza two years ago.
Kipchoge was even able to wave to the crowds as he sprinted towards the finish line, where his wife Grace greeted him.
In jubilant scenes Kipchoge was somehow able to keep running as he celebrated with the crowd before being hugged by his INEOS team-mates.
Afterwards he told the BBC: ‘I am feeling good. After Roger Bannister in 1954 it took another 63 years, I tried and I did not get it.
‘After 65 years, I am the first man! I want to inspire many people, that no human is limited.’
Kipchoge warms up on the start line ahead of beginning his record marathon attempt
The Kenyan marathon man was attempting to run the first sub-two hour marathon in Vienna
Kipchoge runs with seven of the 41 pace-setters who helped him to reach his target
The pacer car fires a fluorescent green laser beam onto the road to mark where he needs to be
Kipchoge and his pacemaking team follow the timing vehicle as it emits a green laser
He had been greeted with a misty autumnal morning and a smattering of fans on Saturday for his bid to run an unofficial sub-two hour marathon.
The 34-year-old marathon world record holder completed the first 21 kilometres in 59.35 minutes, 11 seconds under the two-hour pace.
However, there were a few spots of rain which had not been expected and which could have hampered his attempt.
Kipchoge was being guided by rotating seven-man teams of pacemakers, many themselves world class runners, and by an electric pacecar which showed the ideal pace and the position they should be running.
The highly controlled attempt to break the two-hour barrier consists of 4.4 laps of a 9.6 kilometre course, including a long straight with a loop at each end.
The sport’s governing body, the IAAF, will not recognise the run as an official record because it is not in open competition and it uses in and out pacemakers.
Kipchoge, the reigning Olympic champion who set an official world record of 2:01.39 at the Berlin marathon in September last year, missed out by 26 seconds when he previously attempted to break the two-hour barrier in Monza in May 2017, a race run without spectators.
They will also follow an electric pace car that emits green lasers to show Kipchoge where he needs to be in order to beat the record.
A smattering of crowds gathered in Vienna to watch the sub-two attempt on Saturday morning
The runners make their way past the Lusthaus on a chilly autumnal morning in Austria
The laser will actually be set at a time or 20 seconds below the two-hour mark, ensuring that Kipchoge will be ahead of the target and thus not denied his prize by a stumble.
In Monza, the scientific support team was put together by Nike.
This time, British billionaire Sir Jim Ratcliffe, through his company Ineos, is funding Kipchoge’s shot at history.
As in Monza, Kipchoge is running in the Vaporfly, a Nike shoe containing a highly controversial carbon-fibre plate in the soles, supposedly capable of improving times by one per cent over any other shoe.
Kipchoge ranks the ‘sub-two’ – one of sport’s great unconquered frontiers – as ‘like man landing on the moon’.
This week he said that it would ‘show to the world that when you focus on your goal, when you work hard and when you believe in yourself, anything is possible.’
Last September he ran the distance of 26 miles and 385 yards in the Berlin Marathon just 99 seconds outside the two-hour mark, shattering Kimetto’s record by a minute and 18 seconds. In April, he eased away from Sir Mo Farah soon after crossing Tower Bridge, finishing in 2hr 2min 38sec.
Britain’s richest man and founder of INEOS, Jim Ratcliffe, watches on in Vienna