10,000-Year-Old Man-Made Submerged Monolith Found

The underwater monolith.

After seeing the monolith appear on the high-resolution maps, the researchers sent divers underwater to get photos and video of the peculiar object. Notice the large hole at its end with diameters of about 16, 20 and 24 inches. It's likely these holes were man-made, the researchers said. (Image: via Emanuele Lodolo, Zvi Ben-Avraham)