This gold bar has been found by a 16 year old girl, on holiday in Germany, while she was swimming in a lake.
The teenager found the gold bar, two metres under water, in Lake Koenigssee.
It's in an area called Bavaria in south East Germany.
She handed it into police who are now investigating where it came from and who owned it.
Police divers checked the area for more gold but didn't find anything.
The gold bar has distinctive markings which show the weight of the bar and how pure the gold is.
This has helped experts work out that the gold bar is worth a whopping £11,500.