When most of us picture Australia we think of kangaroos, koalas, and Crocodile Dundee. A nation confused with being a continent and filled with exotic and adorable creatures and even more adorable accents.

But there’s a dark side to Australia that has nothing to do with its population of outdoorsy, Fosters swigging, Vegemite eating folks.

Since being “discovered” by Dutch explorers in 1606, and later settled by the British in 1770, Australia has proven time and again that it never really had much interest in having human beings living there. Of the top ten most venomous animals ever discovered, half of them live in the Land Down Under and that’s just mentioning the venomous creatures. There’s plenty of non-venomous beasties, like the ornery cassowary, that would love nothing more than to eviscerate every human on the continent. Country. Whatever.

Given the sheer quantity of creatures that are just out to get you, it’s a wonder that there were people there to begin with, but there were. Australian aborigines developed a deep respect for nature involving animistic ritual and a rich oral tradition – which probably could be summarized with, “Bob’s dead ‘cause of this weird bug. Better tell everyone about it.”

Today we’ve got modern science to tell us just how deadly every creature in Australia is, and what science says is truly horrifying. Here are 15 of the most terrifying things ever found in Australia.

15. Funnel-Web Spiders

Imagine you’re about to go out for a run. You slip your foot in your shoe and feel an immediate and terrible pain. Then you feel a chill, goosebumps break out, your leg starts to twitch and you’re suddenly foaming at the mouth. You sweat, your heart starts racing, and in minutes you’re vomiting everywhere. Then you pass out. If anti-venom isn’t applied within 30 minutes you could be dead.

That’s what Australians have to keep in mind before they decide to go on their morning jog. The Australian funnel-web spider has some of the most toxic venom of all spiders, and just love to make their webs in people’s shoes. For this reason, Australia has developed anti-venom that has greatly reduced the odds of dying from funnel-web spiders, although envenomations still do happen every year.

14. Stonefish

So-called for their stoney disposition, as well as the fact they look like a rock covered in coral, the stonefish is endemic to most areas of the Indo-Pacific. And as you might have guessed is one of the most venomous fish in the world.

In this case their incredible camouflage makes them also incredibly dangerous to snorkeling tourists. Without even realizing it a swimmer could easy try to grasp a stonefish and get a fist full of venomous barbs for their trouble. They also enjoy shallow waters so you could just as easily step on one accidentally and get a foot full of venom.

The stonefish’s sting is said to be extremely painful and potentially fatal. Antivenom is available, and there’s also a home remedy for more mild stings: poor warm water over the wound. Apparently, the venom breaks down in 45 °C water and can be helpful for the swelling.

13. Saltwater Crocodiles

They may not be venomous, but saltwater crocodiles don’t need to be simply because they can grow to be the size of a small car. They are, in fact, the largest reptile in the known world as well as one of the largest predators on Earth.

Why are they so dangerous? Two reasons: first, they have the most powerful bite in the animal kingdom, able to put out 16,414 N of force in one chomp. That’s basically the same amount of force as an industrial compactor, except all at once and with teeth. Second, they see people as food and have been known to leap out of the water to capture an unsuspecting (or drunk) human to turn into breakfast.

Between 1971 to 2013, Australia reported 106 fatalities due to saltwater crocodiles.

12. Box Jellyfish

Also known as the “sea wasp”, box jellyfish produce an extremely potent venom that is not only extremely painful but also potentially deadly. There are several species of box jellyfish, but the chironex fleckeri is described as “the most lethal jellyfish in the world” and just so happens to call the waters off Australia its home.

Once stung, the pain is described as excruciating and accompanied by an intense burning sensation like your skin was set on fire. The venom acts by causing the cells to become porous enough that their natural potassium leaks out, causing an elevated level of potassium in the bloodstream. While rare, this can lead to cardiovascular shutdown – a heart attack.

Should you survive your encounter with the box jellyfish you’ll likely be left with some intense welts, often leaving scars.

11. Harpoon Snails

I know what you’re thinking: snails can be dangerous? It’s true, and for good reason. The seafaring cone snail is also known as the harpoon snail since it shoots a venomous barb at its prey. The barb contains a potent neurotoxin that instantly immobilizes its victim and allows the snail to slowly approach and swallow it whole.

The smaller species of harpoon snail are no more dangerous or painful than a bee sting, but the larger species, such as conus geographus (geographic cone snail) are known to be fatal to humans. Some researchers estimate that the geographic cone snal is the most venomous creature in the world, and worse still, there is no anti-venom yet developed for it.

It also goes by another name: “the cigarette snail”, so called because you’ll only have time to smoke a cigarette before you die.

10. Blue-Ringed Octopus

Whoever decided to pick that octopus out of the water is a lunatic. The blue-ringed octopus is, as usual for Australia, one of the most venomous creatures on earth. The worst part is that its bite isn’t painful at all, and victims are left dazed and confused as they’re quickly paralyzed.

The risk here is obvious if you’re in the water as you’ll drown, but the true danger is how the victim can’t call out for help. Severe envenomations can also shut down the respiratory tract causing suffocation. There is no known antivenom either, so if you’re bitten by a blue-ringed octopus your only hope is you get rushed to the hospital to be put on a ventilator ASAP. If you survive the first 24 hours you’ll likely make a full and complete recovery.

9. Paralysis Ticks

Even the ticks can kill you in Australia, although they’re more likely to kill your dog or cat. Ixodes holocyclus is the specific species whose bite also contains a neurotoxin that can cause paralysis. It doesn’t always, as the amount of neurotoxin a tick can deliver is very small so a person would have to be particularly susceptible to it in order to become paralyzed, but it does happen.

Symptoms usually set in within 2-3 days after the initial bite. Localized numbness then proceeds to the limbs becoming paralyzed before moving on to the rest of the body. If the victim doesn’t then get to a hospital to be put on a ventilator death occurs due to respiratory failure. Treatment involves finding and removing the tick and then receiving anti-tick serum, and the sooner the better.

8. Giant Centipede

Ethmostigmus rubripes, or the giant centipede, is a unique combination of venomous and terrifying. It might seem impossible for anyone to get over the heebie-jeebies long enough to come within striking distance, however, the giant centipede is also a master of stealth and can sometimes seek shelter in a pant leg.

If it does, and you thoughtlessly try to dislodge it from its new home by putting your leg inside, it can bite. The giant centipede’s mandibles are modified to be slightly hollow, and can deliver a potent venom to whatever or whoever it bites. This is useful to both subdue prey and also discourage pesky humans from trying to evict it from jeans.

The bite is not usually fatal (unless you’re allergic), but has been described as “extremely painful” as well as traumatizing since they’re large enough to eat snakes.

7. Irukandji Jellyfish

Chironex fleckeri is the most venomous jellyfish around and has certainly been known to cause plenty of painful stings, but there’s a simple solution that most Australians have begun to employ: nets. The box jellyfish is relatively large, and netting off public beaches usually prevents them from stinging unwary tourists.

Nets aren’t really an option with the Irukandji jellyfish. The bell of the jellyfish is often less than an inch in diameter, and their stinging tentacles can be as long as a meter (that’s 3.3 feet). They’re small enough to pass through nets and have invisible tentacles that can sting with the potency of 100 cobra bites.

The sting isn’t initially painful, but within 30 minutes symptoms will develop, including muscle cramps, severe pain in the back and kidneys, intense burning, headaches, nausea, restlessness, sweating, vomiting, increased heart rate and blood pressure, and a general sense of impending doom. I am not making that last one up – people have been known to commit suicide from Irukandji stings.

6. Inland taipan

From world’s most venomous snail to world’s most venomous jellyfish, Australia loves its venomous creatures. Naturally, it also has the world’s most venomous snake.

And we’re talking about a truly toxic animal. The inland taipan doesn’t just have one toxin in its venom: it has dozens of chemicals that attack all aspects of the body, from the blood to muscles and kidneys, and even the brain. Death can occur in as little as 30 minutes, and even with anti-venom applied in time there are plenty of lasting complications that can come from an inland taipan bite.

One little Queensland boy, pictured above, spent 10 weeks in hospital after receiving a bite from a taipan. He first suffered a heart attack, and then a brain injury, not being able to see or speak for weeks. He then spent months in physical therapy just to be able to walk again, but has never regained full mobility.

5. Bull Shark

Australia may be home to the biggest shark in the world, the great white shark, but it’s the bull shark that is considered to be the most dangerous shark to swimmers in Australia’s waters.

Bull sharks prefer warm, shallow waters where they ambush fish and rays. They also have a natural camouflage and prefer brackish waters which can make them hard for swimmers to spot, and the fact they prefer the same water as tourists mean the two can come into contact with deadly consequences.

On top of that, the bull shark is a territorial animal and prefers to not have random people swimming around its hunting grounds. The bull shark will aggressively attack intruders, which are thought to be the leading cause of bites. Worst of all, they can survive in freshwater and are sometimes found in freshwater streams, like the one pictured above.

4. Bull Ant

From bull shark to bull ant, Australia likes its bulls. Or not, as there’s nothing to like about the bull ant.

As you’d expect from everything else on this list, the bull ant is venomous. It has a painful sting that is often compared to a wasp, and just like a wasp, it will sting multiple times if it feels threatened. It also has powerful mandibles that it will use to provide a painful bite, although still far less painful than the sting.

Fatalities from bull ants are rare but have been recorded. The risk mostly comes from accidentally stumbling into a bull ant nest, in which case the ants will swarm and attack the intruder. Wearing clothing is not always a defense, as the stinger is long enough to pierce through all but the thickest of denim.

Also, some species jump. Good luck sleeping tonight.

3. Gympie Gympie

Australia is home to so many venomous creatures that the plant kingdom also decided to get in on the action. The gympie gympie tree isn’t necessarily going to kill you with its venomous barbs, but it may inflict so much pain that you’ll kill yourself just to get away from it. Hence the nickname of “suicide plant”.

The gympie gympie is a species of stinging nettle that grow large, innocuous-seeming leaves, but it’s those leaves that deliver the venom as they’re covered in microscopic barbs that are hollow and act as tiny syringes. A single brush will leave dozens of barbs embedded in the skin which all release venom over time.

Unlike most animals on this list, the venom does not result in paralysis and only inflicts agonizing, enduring pain, which can last for weeks if untreated. Check out what happens when this helpful Aussie brushes a single finger on the gympie gympie leaf.

2. Eastern Brown Snake

Not only does Australia call itself home to the most venomous snake in the world, it’s also home to the second most venomous snake in the world.

Although unquestionably dangerous, the inland taipan rarely bites people. It’s a solitary and shy snake that prefers to slither away slowly rather than fight. The eastern brown snake, on the other hand, is fast and aggressive and will not hesitate to bite even if mildly annoyed. Worst of all, their habitat includes all of urban Australia. Of all snake bites reported in the country, the eastern brown snake accounts for 60% of them.

Much like the taipan, the eastern brown snake’s venom is a potent cocktail of toxins causing diarrhea, dizziness, convulsions, kidney failure, paralysis, and cardiac arrest. Fortunately, you’ve got about a day to get some anti-venom in you rather than the taipan’s 30 minutes.

1. Redback Spider

North America has its black widow, Australia has its redback spider. They even both have red markings on their abdomen to remind you of the relation.

Just like black widows, redback spiders are small spiders that love to make their nests in people’s houses. Interaction with humans is so common that the redback can be blamed for as many as 10,000 spider bites requiring antivenom per year. And although they’re related to the black widow, symptoms of a bite can be far worse, starting with a mild burning sensation that progresses into pain and swelling within an hour.

One in three bitten develops systemic envenomation which is when the real fun begins. Nausea, vomiting, abdominal or chest pain, agitation, headache, generalized sweating, and hypertension are all reported symptoms. Severe pain usually lasts for 24 hours, but symptoms can last for months. Rarely a bite can include seizures, coma, and respiratory failure.