This ultimate pub crawl covers 24,727 pubs across 45,000 kilometres and would take three years to complete — that's a lot of drinking.

Who'd have thought science would be the linchpin of the world's most epic pub crawl? Mathematicians have combined to plot a meticulously-planned route taking in almost 25,000 UK pubs.

And aside from the toll the marathon would take on your liver, it would also cost you three years of your life to complete it.

That's what researchers led by Professor William Cook from the University of Waterloo in Canada took two years to discover with their UK24727 project which plotted the shortest possible walking tour through 24,727 pubs in the UK.

It's an example of what's known as the "travelling salesman problem" (TSP), which aims to work out the shortest route between any number of locations, before then returning to the starting point. It's handy for salesmen working out the most efficient way to cover their patch, and for routing deliveries, researchers said.


After crunching the numbers, and using pubs featured on website Pubs Galore and turning to Google maps, the researchers came up with the figures.

"The optimal tour has length 45,495,239 metres (45,495km)," they found — more than the circumference of the earth.

Then they came with an interactive Google map outlining the route, with so many red-pinned pubs on it, those who think they're up to the task will be seeing more than double.

The average distance between pubs is an hour.

And while imbibing at enough of the pubs might mean pub-crawlers think they have the ability to walk on water, the sober research team thoughtfully included scheduled passenger ferry times in the finished product — it streamlines the path to venues on the Isle of Man, Northern Ireland and the islands of Scotland.

It's going to take a while to get out of London: A plethora of red-pinned pubs along the Thames.
It's going to take a while to get out of London: A plethora of red-pinned pubs along the Thames.

At least it keeps pub-crawlers from getting behind the wheel.

Despite what dedicated pub-crawlers might like to think, researchers did not perform the task solely to ease the path of eager pub visitors.

"We, of course, did not have in mind to bring everything mathematics has to bear in order to improve the lot of a wandering pub aficionado," said Professor Cook.

"Rather, we use the UK pubs problem as a means for developing and testing general-purpose optimisation methods. The world has limited resources and the aim of the applied mathematics fields of mathematical optimisation and operations research is to create tools to help us to use these resources as efficiently as possible."

The project represents the largest road-distance "travelling salesman" problem solved to date, with 100 times more stops than any previous projects, the research team says.

It's unknown whether another research team is now studying the epic-ness of the hangover.

Or hangover cures, for that matter.