A bizarre optical illusion in the northern Greek city of Thessaloniki has everyone on the internet talking about it after tourists spotted what appeared to be ships floating in the air on a sunny day.
The large vessels seemed to drift lazily across the air above the waterline, violating the laws of physics.
However, keen observers may notice that the strange sight is in fact a trick of the light, played on the viewer by the inversion of warm and cool air.
The phenomenon has occurred in a few parts of Greece, such as the western side of Samothrace.
The mirage is thought to be the source of the legend of the Flying Dutchman, according to Jonathan Eyers' 2011 book Don't Shoot the Albatross!: Nautical Myths and Superstitions.
The mirage is not limited to the sea, and can be responsible for many unusual sightings, including mountains that appear to be hovering.
Frata Morgana is the Italian name for Morgan le Fay, the Arthurian sorceress believed to use withcraft to conjure up fairy castles used to lure sailors to their deaths.
Multiple 'floating ships' have been photographed and videoed over the years, with boats appearing to hover off the coat of Britain in Cornwall, Devon and Aberdeenshire in once incident.
In another sighting, four ships appeared to hover above the sea off the coast of Cyprus, forming a line just east of the southern city of Limassol.
However, here are photos of the optical illusion in Thessaloniki, as provided by GRTimes.
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