If you’re off adventuring around the world, these are reptiles and monster lizards you most definitely do not want to run into.

The creatures on this list are as close to modern-day dinosaurs as it gets. These dangerous reptiles pose a threat to all species of prey, humans and wildlife alike.

We’ve shown you the most dangerous animals you can find in your backyard and the most shark infested beaches in the world. Now, come with us on a wild tour and meet three of the most dangerous reptiles on Earth.

The Gila monster

The Gila monster is actually not that monstrous, size-wise. The Gila stretches to a modest, mildly intimidating 2 feet, which still makes it America’s biggest lizard. But it makes this dangerous reptiles list more for two other reasons. First, the name – it is one of the few species on the planet formally recognized as a monster. The second reason is its venomous nature. The Gila monster holds the distinction of being the only venomous lizard native to the United States and one of only two known species of venomous lizards in North America – the other is its close relative, the Mexican beaded lizard (H. horridum).

Luckily, you are unlikely to feel a Gila’s poison fangs sink into your calf if they are not provoked first. Still, it retains a fearsome reputation boosted by its name and old, unconfirmed tales of human victims in the desert. The Gila is easily identified by its black body marked with natty patterns of pink, orange, or yellow. The lizard shows up in the Mojave, Sonoran, and Chihuahuan deserts of the southwestern U.S. and northwestern Mexico. It gets its name from Arizona’s Gila River basin, where it was first found. It lives an awful long time – up to 30 years. If one does turn nasty and decide to bite you, you will know about it. A Gila bite is highly painful, and its grip is incredibly difficult to break. Find a source of water, because you may have to fully submerge the reptile to break its bite. The Gila latches onto victims and chews ferociously, so neurotoxins can move through grooves in its teeth and into the oozing wound.

Komodo dragon

No lizard that bestrides the Earth may be more deadly than the Komodo dragon. The Komodo dragon is the largest living lizard species: a monitor lizard of the family Varanidae. The monster’s aura of mystique is increased by its rarity. It only exists on the island that shares its name, Komodo, and a scattering of local islands of the Lesser Sunda Islands of Indonesia. Thanks to its bizarre and frightening Jurassic Park looks, it has become a massive tourist attraction up there with Africa’s “big five” (African elephant, Cape buffalo, leopard, rhinoceros and lion).

Just to make the dragon even more monstrous, it stinks. You can smell its pungent, meaty aroma a mile off. Do not go too close because the dragon has been known to attack humans, most notably when provoked. The dragons are also nefarious for digging up the graves of human corpses. Keen to keep Komodo dragons at bay, local Indonesians build their homes on stilts and keep their goats on raised planks. At night, when the dragons get moody, the villagers rarely step beyond the glow of outdoor lanterns. Also, they avoid wearing red that could be mistaken for blood and catch a dragon’s eye, it’s thought. Just to be sure that the dangerous reptiles don’t eat them, the villagers feed them Timor pigs. The lizard grows to 10 feet and reaches a weight of about 300 pounds. Despite their weight, the dragons can run surprisingly fast and strike with a venomous bite. As seen in the video above, all they need is one bite to inflict a long, venomous death on a victim of a much bigger size.

Saltwater crocodile

Australia has a knack of fielding incredibly daunting and dangerous animals, and this dangerous reptile is no exception. You would not want to get too affectionate with a saltwater crocodile, or “salties” as they are affectionately known, because it is Earth’s largest living crocodilian — and, some sources say, the animal most likely to eat a human. Average-size males are mammoth. They stretch 17 feet and weigh 1,000 pounds. Be careful when venturing not only in Australia but also across the eastern hemisphere. Besides northern Australia, the saltwater croc occupies the brackish and freshwater regions of eastern India and Southeast Asia.

Even more intimidatingly, the dangerous reptiles are a superb swimmers and have often been spotted far out at sea like sharks. Of all the beasts in this shortlist, it may be the scariest – the one you would least like to meet on a bare patch of ground or in some salty lake. The way it operates is it hovers with patient opportunism under the surface near the water’s edge, waiting for prey to pause for a sip of water. A saltwater crocodile will devour anything it can. Its menu includes monkeys, wild boar, water buffalo, and even sharks. On the hunt, a saltie bursts from the water with a thrash of its giant tail, grabs the victim, yanks it underwater and holds it there until it drowns. Saltwater crocodile population estimates go as high as 300,000 worldwide. They are seen as at low risk of extinction. No surprise there. That said, as applies to so many animals, human incursion on its habitat is starting to pan out as pressure.