Thanks to BBC News for this:
This week UNESCO announced it has found three new shipwrecks, including two that are thousands of years old.
But just how many more could be out there?
There are several databases of the world’s shipwrecks, each of which has a slightly different estimate for the total number that has been found.
The online service wreck site has a catalogue of 209,640 boats known to have sunk, 179,110 of which have a known location.
The Global Maritime Wrecks Database (GMWD), on the other hand, contains the records of more than 250,000 sunken vessels, though some of these still haven’t been found.
According to one estimate, around 15,000 ships sank during World War Two alone – there are forgotten battleships and tankers strewn from the Pacific to the Atlantic, gradually bleeding oil, chemicals and heavy metals into the surrounding water as they decay.
In fact, it’s thought the shipwrecks that have been documented only represent a small fraction of the total.
According to an analysis by Unesco, there are over three million shipwrecks resting undiscovered in the world’s oceans.
Bermuda. With more shipwrecks per square mile than anyplace on the planet, Bermuda is the wreck capital of the Atlantic. The island’s razor-sharp coral reefs are to blame for most of the sunken ships, which number over 300 in surrounding waters.