Here are 10 of the most unbelievable discoveries that have been made underwater. [1]9 Ancient Underwater City Of PavlopetriDiscovered in 1967 by Dr. Nic Flemming, this port town from the Neolithic era can be found off the southern coast of Greece. [2]Neolithic pottery is one of the most notable finds in this underwater city. 8 Underwater RiverBlack SeaAt the bottom of the Black Sea, there is an entire ecosystem with a running river, trees, and waterfalls! 7 Zhemchug CanyonBering SeaIf you thought the underwater river was impressive, you’ll love this underwater canyon.