Athletics' last great barrier is staring down the barrel of a gun held by Eliud Kipchoge.

Epic episodes of history have enveloped Vienna over the centuries, but now just one man - as opposed to hoards of foreign invaders - will hope to conquer the city through the arterial Prater park.

The INEOS 1:59 Challenge will mark Kipchoge's second attempt to become the first human being in history to run a marathon - 26.2 miles or 42.2 kilometres - in under two hours.

The Kenyan is the official world-record holder with a time of 2:01.39 from last year's Berlin marathon, but also clocked 2:00.25 as part of Nike's 'Breaking2' project in 2017.

There are a few key differences from that prior effort at Monza: the pace-making tactics have been refined, the surface has been given TLC to the tune of thousands and a live crowd will be giving their support.

Kipchoge believes more than ever

But perhaps most importantly, Kipchoge has come to realise that breaking that mythical two-hour barrier is truly within the realms of human achievement.

The great man's coach, Patrick Sang, faced the media on Friday afternoon and explained the lessons learned from that Herculean attempt two years ago.

"We're learning more every week and we learnt a lot from Monza," Sang reflected with a precision to each word. "It's given the confidence to believe even more that it's possible.

"The fundamentals for all the preparations for major events are the same as before. But the way I see it, he believes more in himself that he is ready to do it. That sort of belief, you can't quantify it."

Pacemaker Lagat inspired by Monza

One man who joined Kipchoge on the Monza tarmac in 2017 was double world champion Bernard Lagat, who will feature on the Viennese streets as an arrowhead for one of the pacemaking groups.

The American admitted that he couldn't sleep after 'Breaking2' and that those dastardly 25 seconds - less than 200 metres in practice - have both haunted and inspired him ever since.

"I did not sleep that night," Lagat admitted through a smile. "In fact, I had a beer a little bit later! Just one to celebrate and then I thought: 'he did what? 2:00.25?'

"Some people might think: 'that's not achieving what he set out to do,' but to me, he really nailed it. It's just a matter of when you see those 25 seconds, but that is so close. He inspired me so much."

'We're helping him help the sport'

And this is more than just a numbers game.

As the typically spunky Henrik Ingebrigsten kindly reminded us all, Saturday morning's attempt at history has the chance to splash athletics across the world's back-pages for a positive reason.

It would be the Roger Bannister moment of our time and the Norwegian pacemaker was keen to reiterate that, deep-down, Kipchoge is running for the sport as opposed to simply himself.

"We're helping him help the sport," Ingebrigsten eloquently put. "He's not doing this for himself. It's not his wish to be the first person to break two hours, he wants the marathon to be a better event.

"That's what we're doing, we're trying to make the sport better. We're all working together with that thought in mind: to help the sport improve and grow into something even better than it is today."

History beckons in Vienna

The stage is set. The man himself is ready to run the roads, innumerable resources have been assembled and everything has been tailored for optimal speed.

Vienna's Prater is most famous for the 1949 film The Third Man but, in less than 24 hour's time, it's autumnal allies may well be immortalised by Kipchoge becoming the first man to break two.