Scientists discovered an uninhabited mega-city underground after they pumped 10 tonnes of concrete into an abandoned ant hill over the course of three days.

Their endeavours were part of the documentary Ants! Nature’s Secret Power and by the time they were finished it was astonishing to see how large the city the insects had built for themselves was.

While it took three days to pour the concrete into the abandoned anthill, the job to get their mega-city mould back out of the ground was several weeks of careful digging work.

Once they uncovered the shape of the structure, now filled up with concrete, they were able to see just how intricate and complex the construction of this underground city had been.

So just how big is this mega-city created by a million minds?

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The whole thing was 50 square metres in size and went down eight metres underground, creating a giant interconnected series of tunnels and chambers with different rooms for different purposes.

For ants wanting to get around while dodging most of their colleagues there were even side roads for the insects to scuttle around in.

All of this might make you think it was constructed by one mind with a particular goal of how the mega-city should look, but it was instead constructed by 'the collective will of the ant colony'.

Right beneath the ground we walk on thousands of little creatures were toiling together in the dark to scrabble out an incredibly complex construction.

Even more incredibly, while it took 10 tonnes of concrete to fill out the abandoned mega-city experts estimated that the ants shifted a whopping 40 tonnes of dirt to clear out space for their home.

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You might be wondering just how they managed to do that and the answer is that ants are incredibly strong, able to carry between 10 and 50 times their own weight.

Their neck joints in particular can withstand pressure of up to 5,000 times the creature's own weight before giving way.

A big amount of dirt to shift requires a big workforce and with thousands of ants as a construction team this colony was able to construct themselves a mega-city.

However, with the experts discovering the place abandoned your next question might be why ants abandon a perfectly good anthill.

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The most common reasons for a colony of ants to skedaddle from their carefully constructed mega-city beneath the ground is the danger posed either by predators or damaging disasters.

Anthills can be invaded by other ants or creatures that want to break in and feed on the insects larvae, while weather conditions can risk flooding the nest and rendering it unsafe.

If people mess with anthills the colony of insects inside can also get the message that they're not in a safe location, resulting in them upping sticks and moving.