Parts of the third ship were first discovered in October ... shipwreck location from the Battle of Koan. Remains from the Mongol invasions are believed to be scattered across a vast seabed area ...

The Mongol Empire attempted to invade Japan in 1274 and 1281, both during the Kamakura Period (1185-1333). It is believed that about 4,400 ships came to the area in the second invasion attempt.