The Lost Civilization Beneath the Oceans: What Was Erased 50,000 Years Ago?

In 2001, a research vessel scanning the ocean floor off the coast of Cuba made a discovery that shouldn't exist.
They weren't looking for ruins, just doing routine sonar mapping. But what appeared on their screens made absolutely no sense. Symmetrical shapes. Perpendicular angles. Repeating geometric patterns stretching across miles of the seabed, buried under 600 meters of water.