Lost lands

Lost lands can be continents, islands or other regions existing during prehistory, having since disappeared as a result of catastrophic geological phenomena or slowly rising sea levels since the end of the last Ice Age. Lost lands, where they existed, are supposed to have subsided into the sea, leaving behind only a few traces or legends. The term can also be extended to mythological lands generally, to underground civilizations, or even to whole planets.

The classification of lost lands as continents, islands, or other regions is in some cases subjective; for example, Atlantis is variously described as either a "lost island" or a "lost continent". Lost land theories may originate in mythology or philosophy, or in scholarly or scientific theories, such as catastrophic theories of geology.

As the study "Lost Continents" by L. Sprague de Camp seeks to show, many modern writers speculate about ancient civilizations that dwelled on continents now deluged under sea level. According to de Camp, there is no real scientific evidence for any lost continents whatsoever.

In addition to these myths about lost continents there also are various regional legends about lost lands; see e.g. Lyonesse, Cantref Gwaelod (also known as Lowland Hundred), or the legend about Lomea, located at the Goodwin Sands. Unlike the lost continents mentioned above, whose location has been a matter of speculation, these lost lands are associated with specified places.

It is likely that until relatively recent times the Isles of Scilly, with which Lyonesse is often associated, were much larger, many of them being joined into a single island named Ennor. Rising sea levels flooded the central plain around 400–500 AD, forming the current islands.

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