OceanShipwrecks
UNESCO estimates around three million shipwrecks lie on the seabed.
Most have never been located, and the great majority are older than any surviving written record of them.
Source
This fact is written from the English Wikipedia article it links to, so you can check every word in one tap. Fact Drop rates that source 4 out of 5 for credibility, and the rating travels with the fact on the back of its card in the app.
More ocean facts
Ocean facts from a place we have mapped less thoroughly than Mars. A male anglerfish merges with his mate for good, there are lakes at the bottom of the ocean, and below about 8,400 metres there are no fish at all. Each fact links to its source.
- Sensitive instruments are still built from steel salvaged off warships sunk before 1945.
- A male anglerfish merges with his mate. Permanently.
- The Mediterranean dried to salt flats around five million years ago.
- There are lakes at the bottom of the ocean.
- The most abundant photosynthetic organism on Earth was not discovered until 1986.
- The Portuguese man o' war is not one animal.