You might think that the biggest cat in the world is an African Lion like Tao here, whom Stephen met in America.
He's only one year old but he's already enormous.

His strength already is incredible.
At one point Stephen couldn't even get up!

Ha ha!
It's very important for lions to be big because they hunt large animals like zebra.
Just look at the size of his paw!
Tao will keep growing until he's as big as Arthur, who you can see here.

Lions can grow to over 2.8m from nose to tail, making them the biggest cats in Africa.

But they're not the biggest cats in the world!
Gail met Chandra – a beautiful one year old Bengali tiger.

At the moment she's only half the size she'll be when she's fully grown.
A fully-grown adult tiger can actually weigh up to 300kg – that's six times as heavy as Gail!
Tigers have developed an unusual hunting technique involving water.

Most cats hate water, but tigers are really good swimmers.
They actually have webbing between their toes and, given the chance, they'll chase an animal like a deer into the water
That’s because the long, skinny legs of the deer aren't very good for swimming, meaning that the tiger is able to make a catch must faster in the water than on land.
So – tigers may also be big. But even they're not the biggest in the world.

Sudan is!
If you guessed lion or tiger, you weren't far wrong!

That's because Sudan is a mixture of both – his dad was a lion, and his mother was a tiger. That's why this type of cat is called a liger.
If you've never heard of a liger, that's because there are very few of them in existence.

They don't breed in the wild because lions live in one part of the world and tigers in another – so they never meet.
They can be bred in captivity, although not very often.

There are only twelve of them in existence in the world today!
Take a look at Sudan's face.

You can see he's got the face of his lion dad…
…and the stripes of his tiger mum.

But he gets the size from both parents.
He weighs over 400kg –nearly half a tonne!

When he stands on his hind legs he's nearly 4m tall – almost as high as Stephen standing on Gail's shoulders!
He is officially the biggest cat in the world.

A truly beautiful (and big!) brilliant creature!