Only ever seen 4 times Spanish Stonehenge 

It rises from the bottom of the reservoir from an ancient structure called Spanish Stonehenge near Madrid.

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This is believed to be a prehistoric stone circle.

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If it is seen, then around 5,000 BC had pleased archaeologists.

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This was actually first discovered in 1926.

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It was filled in 1963 by making Valencenes Reservoir.

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In this the stone was fully visible only four times.

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Spain is facing the worst conditions in these 60 years and the water has receded again.

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