A drought in Spain has revealed an ancient stone circle that usually stands hidden beneath the waters of the Valdecañas Reservoir in western Spain. But the so-called “Spanish Stonehenge” is just a small piece of an ancient Spanish landscape flooded by dam construction in the 1960s.

The dolmen of Guadalperal

The exposed rocky floor of the reservoir today is punctuated by about 150 granite stones in concentric oval rings around a chamber about 5m wide, meant to be entered through a megalith-lined passage facing east. It has earned the nickname “Spanish Stonehenge,” but that’s something of a misnomer. Unlike Stonehenge, Guadalperal wasn’t built as an open-air monument.

The standing stones visible today are the framework of a burial mound. Once, the spaces between the concentric rings would have been filled with earth and pebbles, and the vertical stones would have supported a roof of horizontal slabs. An earthen mound would have covered the whole thing; you can still see the remains of that structure in the bank of sand and gravel that now surrounds the standing stones.