Death Valley (image: Death Valley sand dunes): Has its name for a reason. Spend too much time in the area the hottest, driest and lowest place in North America and you'll learn why early settlers bestowed such a forbidding name upon the place. Nestled between steep mountains, Death Valley stretches for 140 long, hot miles (225 kilometers), and lies 282 feet (86 meters) below sea level. In July, temperatures hover around 115 degrees Fahrenheit (46 degrees Celsius). The scorched valley boasts the second-highest temperature ever recorded, a stunning 134 F (57 C) in July of 1913. Make sure to bring plenty of water if you visit. Large parts of the valley have no cell phone coverage, so you may not be able to call for help. Have you visited Death Valley in North America?

Australia (image: Australian saltwater crocodile): This continent is rife with biting beasts that may not steal your eternal soul but can definitely do some nasty things to your corporeal parts. It's the only place on Earth where venomous snakes outnumber non-venomous snakes. Australia's brown snakes and tiger snakes can kill humans with a single strike, but life-saving anti-venom treatments are widely available. However, no amount of anti-venom can protect against the saltwater crocodile, one of Australia's most dangerous animals. Common in the northern Outback, the crocodiles kill one or two people a year. They are monstrous; the largest males can grow up to almost 23 feet (7 meters) long, and they are very aggressive. Add to that the infamous great white shark and a host of venomous creatures the deadly box jellyfish, the blue ring octopus, the creepy-looking stone fish, dangerous spiders and Australia lives up to its reputation as a spot that will toughen you up if it doesn't kill you first. Have you ever visited or lived in Australia?

Antarctica (image: Dumont d'Urville station): During the Antarctic winter, darkness rules the land. From late March until mid-September, the sun never appears above the horizon, vicious blizzards can reduce visibility to just a few feet, and temperatures stay around or below minus 76 F (minus 60 C). Vostok Station, a Russian research center, holds the record for the lowest temperature ever recorded at the surface of the Earth: minus 128 F (minus 89.2 C), in 1983. If you don't freeze to death on the southernmost continent, you might die of loneliness. Antarctica is the only continent on Earth with no native population. Only scientists and adventurers spend time in this windswept, frozen, forsaken place. Do you know of anyone that has been to Antarctica?

Komodo Island, Indonesia (image of a Komodo dragon): On Komodo Island no one can hear you scream, at least the Komodo dragons can't. Their ears can't pick up high-pitched frequencies like a human howling in pain, but their tongues can smell you, even if you are hiding a couple of miles away. The largest lizards in the world, these cannibalistic, scavenging, predatory monsters would do well in a B-grade horror movie. Not only are they big and scary-looking, they're also just plain gross. The largest recorded Komodo was 10.3 feet (3.13 m) long and weighed 366 pounds (166 kg). Komodo dragons eat carrion, but they also hunt, attacking everything from smaller lizards to rodents to water buffalo. To kill, the Komodos will knock an animal off its feet and tear it to pieces. If the Komodo's large, serrated teeth don't do the trick, the venom and deadly bacteria in a Komodo's saliva will kill any animal that escapes within a few days, and the dragons can then feast on the carcass. The lizards are efficient eaters, polishing off bones, hide, hooves, even intestines to clean out the feces of their victims, they vigorously swing the innards around. Since Komodo dragons are cannibalistic, juveniles often roll in fecal matter. The smell keeps the bigger adults from turning the little ones into breakfast. Have you seen a Komodo dragon in a wildlife sanctuary or zoo in the area where you live?

Gomantong Cave, Malaysia (image: entrance of Gamantong cave): Like a self-contained horror film, in this cave, the darkness is alive! If the millions of bats don't creep you out, maybe the millions of cockroaches feasting on massive mounds of bat guano will. And the roaches don't just eat the guano. Bats or birds foolhardy enough to fall into the heaving mountains of insects are quickly devoured, their tiny bones picked clean by the insatiable cockroaches. However, there is some poetic justice at work. Enormous, cockroach-eating centipedes skitter across the cave's walls. And so the circle of life, in all its beauty, rolls onward. Don't get caught in here without a flashlight. Or perhaps a completely-sealed space suit. Would you be adventurous enough to go inside the Gomantong cave?