14 Mysterious Landmarks That Science Still Can't Fully Explain

7. The Yonaguni Monument (Yonaguni, Japan): Submerged Structural Debate

Off the coast of Japan, the Yonaguni Monument is a colossal, submerged rock formation featuring perfectly straight lines, right angles, flat surfaces, and terraced structures. While some geologists contend it's a natural geological formation shaped by seismic activity and currents, its striking resemblance to ancient human-made structures, including steps and even carvings, leads others to believe it's the remnant of a prehistoric civilization. Without definitive archaeological evidence or inscriptions, its origin remains a captivating debate, submerged beneath the waves of scientific uncertainty.