Lost continent

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.

Although the existence of lost continents in the above sense is mythical, there were many places on earth that were once dry land but submerged after the ice age around 10,000 BCE due to rising sea levels, and possibly were the basis for neolithic and bronze age flood myths. Some others were lost due to coastal erosion or volcanic eruptions. Approximately listed by size, these are:

Phantom islands, as opposed to lost lands, are land masses formerly believed by cartographers to exist in the historical age, but to have been discredited as a result of expanding geographic knowledge. Terra Australis is a phantom continent. While a few phantom islands originated from literary works (an example is Ogygia from Homer's Odyssey), most phantom islands are the result of navigational errors.

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