Eliud Kipchoge just ran a marathon in 1:59:40.

The Kenyan is the first person in history to run a marathon in under two hours.

It's the biggest milestone in long-distance running since Sir Roger Bannister ran the first sub-four-minute mile at the 1952 Olympics.

Kipchoge was supported by a rotating team of 41 pacesetters, meaning his time will not count as an official record under IAAF conditions.

He does hold the official record already, though, after running 2:01:39 in the 2018 Berlin Marathon.

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Eliud Kipchoge from Kenya just became the first person in history to run a marathon in under two hours.

Kipchoge ran 26.2 miles in 1:59:40 at the Ineos Challenge in Vienna, Austria on Saturday.

"I am feeling good. After Roger Bannister in 1954 it took another 63 years, I tried and I did not get it — 65 years, I am the first man — I want to inspire many people, that no human is limited," the runner told the BBC after the marathon.

Kipchoge was 10 seconds ahead of schedule at the halfway mark, whereafter he slowed slightly but never ran a kilometer slower than 2:52 throughout the race.

The course in Vienna was specially chosen for its favorable running conditions — there was just 2.4 meters of incline over the entire route.

The 34-year-old was supported by a rotating team of 41 pacesetters and a pace car that beamed lasers onto the road.

Eliud Kipchoge running with his pacers in Vienna. BBC Sport

He was also handed drinks and energy gels from a bike every 3.1 miles.

These conditions mean Kipchoge's time will not stand as an official record as they do not conform to IAAF rules.

Kipchoge does hold the official record already, though, after running 2:01:39 in the 2018 Berlin Marathon.

He previously attempted the sub-two-hour marathon in 2017 at the Monza grand prix circuit in Italy, as part of Nike's Breaking2 project, but failed by just 25 seconds.