How to make a crocodile smile:

How to make a crocodile smile: Swim in a pool full of deadly salties with just a perspex cage for protection

Tourists to this unusual theme park are sure to get some holiday snaps with a difference.

Inspired by the popularity of cage shark-diving, a tourist attraction has opened that allows adrenalin junkies the chance to swim with killer crocodiles.

And, as these incredible pictures show, participants can get up close and personal with one of the worlds deadliest creatures.

Definitely no running, ducking bombing or petting in this pool: Face to face with one of the 125 stone monsters

All that separates thrill-seekers from the huge saltwater crocodiles is a five-inch thick perspex box that has, we are assured, undergone 'extensive' safety testing.

Fearless participants climb into the clear container - nicknamed the Cage of Death - which is suspended on a monorail track that runs above four crocodile enclosures.

Two grated doors lock into position on the top of the 10ft tall box which is then lowered into the water and comes to rest 2ft beneath the surface.

To ensure that the paying customers get their money's worth, chunks of meat are tied to the bottom of the cage. The crocodiles instantly drawn to it when it enters the water.

The results vary from the crocs 'eye-balling' the swimmer, rubbing against the cage or going into a full on 'aggressive attack' against it.

Snappy snaps: Holiday photos from this resort will be just a little different

Customers pay about £100 to spend 20 minutes swimming alongside the crocs; the largest of the beasts measures a whopping 18ft and weighs over 125 stone,  

One of the mighty reptiles at the Crocosaurus Cove park in Darwin, Australia, is named Burt. Film buffs might remember him from the first Crocodile Dundee movie - he's the one who nearly ate Linda Koslowski's character.

Sallie Gregory, spokeswoman for the park, said: 'Many people find the opportunity of getting to within a few inches from the jaws of these crocodiles exhilarating.'

'People often get activity ranging from an aggressive attack to a casual eye-balling and swim past where the crocs are so close that they rub against the cage.'

'Most of the women who take part say they are happy just to watch the crocodiles while guys tend to want the action and attack.' 

Smile please: Two thrill-seeking tourists get up close and personal with one of the saltwater crocodiles at the Crocosaurus Cove park in Darwin, Australia

She added: 'One of our directors who has extensive experience with crocodiles wanted a concept that allowed people to get up close to these ultimate predators in a safe environment.'

'The cage runs on a overhead monorail system, suspended over the enclosures and is lowered into up to four separate enclosures as part of the 20 minute experience.'

'The perspex is about 135mm thick and extensive testing in both the manufacturing and the way the crocodiles would react to the cage were carried out prior to the testing team entering the cage.'

The 'Cage Of Death' has been extensively tested for safety. With one of these prehistoric killers just inches away, one might hope so..

'The top of the cage has two grated doors to stop anything entering the cage and a back up motor and separate chain operates to ensure that in the event of a malfunction, the cage can continue to operate.'

'The cage generally allows about two feet from the surface of the water though this can be adjusted if people are not strong swimmers and would prefer to keep their head above water.'  

Among the crocodiles people can swim alongside are the mating pair of Houdini and Bess as well as Chopper, Denzel and of course movie star Burt.

But one of the most popular crocs is Wendell  - he's the biggest and is named after muscular Australian rugby star Wendell Sailor.

Crocodile attacks in the wild are quite rare these days. However, during the Japanese army's retreat from Ramree Island in February 1945, saltwater crocodiles are thought to have been responsible for the deaths of 400 Japanese soldiers. 

British troops encircled the swampland through which the Japanese were retreating, resigning the Japanese to a night in a mangrove swamp which was home to thousands of saltwater crocodiles. 

The Ramree crocodile attacks are listed as 'The Greatest Disaster Suffered from Animals' in The Guinness Book of Records

Saltwater crocodiles are the largest reptiles on the planet. Their main habitat is northern Australia and New Guinea, Indonesia and Borneo. They have been known to kill and eat horses, water buffalo, and even sharks as well as the occasional human.