World’s biggest iceberg is almost as tall as The Shard and weighs 1,000,000,000,000 tons

The world's largest iceberg is a staggering three times the size of New York City and is almost as tall as the UK's biggest skyscraper, The Shard.

That's more than twice the size of Greater London - It's almost impossible to imagine iceberg so large.

It has the rather boring name of A23a, and it broke away from the Antarctic coast in 1986.

Since then it has remained anchored on the ocean floor.

But in recent months, after it began drifting northwards at a rate of around 30 miles per day, scientists noticed that this mega iceberg was on the move.

It's covering some serious distance.

Satellite images have measured the giant block of ice - all thanks to European Space Agency's CryoSat-2 mission - revealing it has a depth of 920 feet (280 meters).

It still remains unclear what direction the giant iceberg will take, but the situation is closely monitored.

It's believed that it could be soon forced through a zone known as 'iceberg alley' as ocean currents and strong winds could force it through that route.

This is a common route for icebergs to float toward the sub-Antarctic island of South Georgia.

However, as it takes this route it becomes a risk to wildlife on the island.

Since the iceberg weights just shy of a trillion tons, (absolutely insane, we know), if it were to grind to a half offshore it could cause harm to penguins, seals and reindeer that live there.

After splitting from the Filchner Ice Shelf in 1986 it quickly relocated in what is known as the Weddell Sea.

For almost four decades before suddenly starting to drift, it remained an ice island there.

A group of scientists on board the RRS Sir David Attenborough came face to face with the iceberg last week and captured it on film.

ndrew Meijers, chief scientist aboard the research ship, said: “It is incredibly lucky that the iceberg’s route out of the Weddell Sea sat directly across our planned path, and that we had the right team aboard to take advantage of this opportunity.

“We’re fortunate that navigating A23a hasn’t had an impact on the tight timings for our science mission, and it is amazing to see this huge berg in person — it stretches as far as the eye can see.”