Top 5 Most Mysterious Underwater Structures Ever DiscoveredWith all our advanced technology, many believe we’ve figured out everything there is to know about our planet’s past. But the fact is that our world is a staggering four and a half billion years old. In that time over 115 billion people have lived here, developed cultures and built massive cities - some of which are now hiding under our oceans, seas and lakes. The next 5 structures likely once existed on land. People, like you and me, perhaps once thrived in them, but at some point, they were swallowed up by rising waters and forgotten by history - that is, until now. Here are the 5 most mysterious underwater structures ever discovered. 5. Lake Michigan StonehengeIn 2007, Mark Holley, a professor of underwater archaeology from the Northwestern Michigan College was with his colleague on Lake Michigan searching for shipwrecks using sonar equipment. 4. Cubas Underwater CityWhile conducting a joint exploration survey with the Cuban government, a Canadian company called Advanced Digital Communications stumbled on what could be one of the most intriguing underwater structures ever discovered. Off the western coast of Cuba, found an astonishing 2000 feet below the water’s surface, the team found unusual structures that strongly hints at a set of organized stones, a lot like you would see in a city or urban area. 3. Baltic Sea AnomalyThis unusual formation or object was first sighted in 2011 when a Swedish treasure hunter and his team, Ocean X, were scouring the Baltic Sea using side scan sonar. Dubbed as the Baltic Sea Anomaly2. Gulf of KhambatOnce known as the Gulf of Cambay, the Gulf of Khambat has become known worldwide as the cradle of civilization. Discovered in 2001 by India's Institute of Ocean Technology while they were conducting a study on pollution, they unearthed one of the most compelling pieces of evidence that mankind and urban civilizations may be much older than anybody previously thought. 1. Japan Yonaguni MonumentTour operator, Kihachiro Aratake first discovered Japan's famous Yonaguni Monument in 1986, when he was scouting for potential scuba diving sites for his company. The underwater formation is thought to be a remnant of an old Japanese civilization, said to have existed about 5000 to 10,000 years ago. Ever since it was discovered, marine geologist Masaaki Kimura has been visiting and studying the formation and he says that the more he visits, the more convinced he is that the structure is actually a remnant from the ancient past.Support the show Learn more about your ad choices. Visit megaphone.fm/adchoices