Ancient CivilizationsUnsolved Mystery Of The Anomalous Underwater Structures Discovered In Minnesota Posted on October 27, 2025 by Administrator Minnesota, famously known as the “Land of 10,000 Lakes,” actually boasts an impressive 14,420 freshwater bodies. Yet, among this vast array of natural beauty, there is one lake that truly stands out and deserves our attention today. The discovery of unusual underwater structures in Minnesota’s waters presents a captivating mystery. Are these formations remnants of a wall, an ancient fort, or something else entirely?