Unsolved Mysteries: Five Enigmatic Wonders of the World

For all our advanced technology and internet sleuthing, there are corners of this earth that refuse to give up their secrets.

Number 1: The Stony Tunguska River, also known as Pekamini Atiune-Goska River. In 1908, an explosion 1000 times greater than the nuclear bomb dropped on Hiroshima tore through the air over Siberia. Witnesses reported a column of bluish light as the sky seemed to split in half and catch fire. The blast sent a shock wave that knocked people off their feet and flattened 770 square miles of forest, toppling an estimated 80 million trees. When the first expedition arrived to investigate, native guides would not enter the impact zone, fearing people they called the Valley Men. Strangely, the scorched trees in the center of the blast zone remained upright. Scientific consensus attributes the blast to the explosion of a meteorite in midair, leading some to blame natural gas and others to blame a collision with an alien spacecraft.

Number 2: The Temple of Jupiter, located in modern-day Lebanon. This ancient temple of Roman design is now a little more than rubble. While the architecture is largely in keeping with the style of the time and therefore not especially mysterious, the temple's foundation is another story. Even after many years of study, experts are at a loss to explain how using the technology of the time, builders were able to displace and position foundation stones weighing approximately 1,000 tons apiece. For context, these are among the largest and heaviest stones used in construction of any kind throughout human history, including today. Theories involve multiple cranes being used in conjunction or rolling the stones using piles of earth, but it's all speculation at this point.

Number 3: The Devil Sea, also known as the Dragon's Triangle and the Pacific Bermuda Triangle. This is a region of the Pacific Ocean that is south of Japan, in which several ships have disappeared, notably the Japanese research vessel Ko Madhu Number 5 in the early 1950s. Japan has declared this a disaster area. Sailors have reported problems with electronic instruments and sightings of unmanned ghost ships. American author and linguist Charles Berlitz, who also popularized the idea of the Bermuda Triangle, made the area around Miyake Island famous with his book "The Dragon's Triangle" in 1989. Although authorities claim that Ko Maru was destroyed by natural forces while the crew was investigating the eruption of an underwater volcano, Berlitz attributed the incident to unknown supernatural forces and even blamed the Dragon's Triangle for the disappearance of aviation pioneer Amelia Earhart.

Number 4: The Door to Hell, also known as the Darvaza Gas Crater. This natural gas field is more formally known as the Darwaza Gas Crater, but that doesn't do it justice. 226 feet wide and 98 feet deep at its lowest point, this hellish-looking pit in the Ahal Province of Turkmenistan is just about the last thing you'd expect to stumble across as you traverse the Karakum Desert. It's thought to have been burning continuously since 1971 when it was intentionally set ablaze for fear that natural gas might affect local towns. Experts expected the gas to burn off in a matter of weeks, but here we are nearly half a century later, and it continues to glow as bright as the fires of hell. Now a tourist attraction, it's especially impressive when seen at night.

Number 5: Eternal Flame Falls, New York, USA. Can't get enough fire? Located in the United States and prefer something a little closer to home, the Eternal Flame Falls in New York State are sure to satisfy. Like something straight out of a fantasy film or video game, this waterfall in Chestnut Ridge Park contains a small grotto where natural gas escapes, causing a small perpetually burning flame. It does occasionally go out and needs a little help to get it going again, but it generally persists unaided year-round. The Door to Hell might be more impressive due to its size, but there's something about the combination of fire and water that makes Eternal Flame Falls uniquely captivating