The way London looks today, it's quite hard to imagine dinosaurs and massive prehistoric beasts lumbering, stomping and roaring through the City.
I guess if you've seen the Juarssic Park films, you might have a better idea of what it could be like, with a huge T. rex going on the loose in New York, bulging right out of the cinema screen.
Either way, it all seems pretty far fetched.
But let's close our eyes for a minute and imagine a London cleared of buildings and roads. Let's go way back to a prehistoric landscape of low undulating hills, bordering a wide river, edged with reeds and muddy swamps.
It was in this pre-London environment that London's prehistoric animals once truly roamed, slithered and stomped.
Under the sea...
Then let's go back even further than that. Back to a time when the site of the future capital was actually under water.
It's hard to believe, but fossils from that time actually still exist, buried way down in the rocks under our feet and etched deep into the stones that make up many of London's great buildings.
Incredibly, the Portland stone that was used to build the Customs House on Lower Thames street for example, still retains a wavy pattern that was once made by the flowing waters of the sea, and there are ancient oyster shells fossilised deep within the stones used to build the British Museum.
Seaweed can still be made out in the stone used to build Waterloo Station and the skeletons of sharks have also been found in the clay that makes up much of the bed on which London has been built - and into which it is very slowly sinking.
But once the oceans receded and the continents as we now know them began to take shape, the area of London would have been home to just about every prehistoric beast under the sun.
What's more, it would have been very easy for these beasts to lumber across from Europe, because Britain was still connected to the continent by a land bridge until some 8,000 years ago.
So what proof do we have for these ancient animals?
A dearth of dinos
Well strangely, while London's Natural History Museum is World famous for its dinosaur bones, and millions have flocked from around the world to see them, the irony is that no significant dinosaur finds have ever been made in the capital.
This is strange given that more than 500 dinosaur fossils have been found in the UK, and possibly 100 species of dinosaurs would have stalked these islands.
So the lack of finds here is probably more to do with the built-up nature of the area more than anything else and we can rest assured that everything from the two-metre high Iguanodon - one of the duck-billed dinosaurs - the armoured Hylaeosaurus and the massive Megalosaurus would have roamed the area we now call home.
If you want to find out more about these beasts a visit to the Natural History Museum is a must.
But for our very own London examples of Prehistoric animals, we have to fast forward a bit to some 200,000 years ago.
At this time, huge elephant-like animals called mammoths were stomping around the London landscape. Roughly the same size as an elephant and weighing up to six tonnes, these massive beasts roamed around using their tusks for fighting and moving objects. They would have grazed on grasses and no doubt drunk from the Thames.
What a spectacle it must have been for the early humans who were here at the time, the Neanderthals, to see.
These early humans were living a nomadic lifestyle in the London area, hunting animals with stone tools and probably moving their camps to fit in with the best hunting grounds and available food and water at any given time of the year.
Quite how these early humans got on with the mammoths is anyone's guess although it's probable they were too large to hunt with stone tools. Instead they may have scavenged them when they died and the hunters would have used the bones and tusks for making art and tools and the fur for clothing.
But how do we know mammoths were ever in London?
A mammoth discovery
It was in the 19th Century at a brickworks in Ilford when huge amounts of clay were being dug out of the soil to make bricks, that their remains first came to light.
In 1834 a senior civil servant named Antonio Brady started what was to become a 40-year long excavation of the area around Ilford.
He would, in that time, discover the remains of more than 300 elephants, and the area became known as the Ilford Elephant Ground.
His specimens even formed the nucleus of exhibits displayed in the Natural History Museum in South Kensington when it opened in 1881.
Eventually the remains of some 100 mammoths were found in the area. This means that back in the prehistoric period the place must have been overrun by herds of the huge beasts.
Among these incredible finds was the very rare discovery of a complete mammoth skull. It was found complete with tusks that were some 3ft long!
Ilford also turned up the remains of some other amazing beasts including elephant and hippopotamus teeth and the remains of oxon, so our mammoths definitely were not alone.
Not alone indeed. Incredibly, the remains of crocodiles have been found buried in the clay of Islington, suggesting these scaly creatures would once have been slithering through the reed beds and tributaries at the edges of the Thames.
Just as amazingly, the remains of a Prehistoric rhinoceros were discovered underneath the law courts at the Old Bailey. The bones of this ancient beast dated back some 60,000 years to the Paleolithic period when England would have been a cold, dry landscape. It was the kind of woolly rhinoceros that would have roamed the area at the time. A shaggy kind of beast whose think wool would have protected it from the cold - not at all like the African ones we see on TV today.
We're so used to seeing hippos roaming around on the African mud flats on television wildlife programmes, that it's easy to think they could never live anywhere else.
But go far enough back in time and they would have been here too. The remains of a hippo dating back some 120,000 years have been found under a quiet suburban street in Brentford. So where people now park their cars and commute too and from jobs in the City, herds of these massive and highly dangerous beasts must have been roaming. That is until brave early humans started to hunt them down with stone tools.
Buffalo skeletons have been located beside St Martin in the Fields church, a brown bear near North Woolwich and reindeer, giant beavers and hyenas have also been uncoveerd. So London clearly was home to a complete menagerie of just about every kind of ancient animal you can think of.
The skulls of wolves have even been found in Cheapside and Shepperton. They date to some 3,400 years ago, a time when wolves would have roamed all over England in packs. The skull dates from the Neolithic period, a time when the first farmers were starting to cultivate land for cattle in a settled way. They would have started to hunt the wolves at this time to keep them away from their livestock.
Beasts of London
Fast forward thousands of years and amidst the civilised chaos that is the City of London, a brand new exhibition at the Museum of London is celebrating London's prehistoric animals and all those beasts, large and small, which have inhabited the City ever since.
Beasts of London takes visitors on an amazing interactive tour through the ages to meet different animals from London's history in an incredibly imaginative show.
The animals all have characters and are voiced by some of London's best known performers.
There are Prehistoric woolly mammoths and Roman eagles, the fleas that carried the Great Plague, urban pigeons and 21st century pets. There are the leopards, lions and tigers that were brought to the City to parade in circuses.
Then there's the urban animals such as foxes which make unexpected homes in the City's streets and alleys and domestic animals like cats and dogs that we so love today.
Each animal has been inspired by objects that the museum has in its collection.
You can find out full details and opening times of the exhibition here .
The exhibition makes clear that teh animals and beasts we have shared our City with continue to fascinate and inspire us, and none more so than the amazing prehistoric beasts that once grazed and hunted where we now work rest and play.
Could there be a time in the future, among the broken down remains of the City as it sinks into the clay beneath, long after humans have left, when the beasts take over once again?