Europe had an exceptionally hot summer in 2019. Seven weather stations in Spain recorded their highest temperatures ever recorded in June, and above-average temperatures and drought were recorded across the country in July and August . However, the scorching weather conditions revealed an unexpected sight in the Spanish province of Cáceres: as drought rolled back the Tagus coastline, a circular monument 4,000 to 7,000 years old emerged in the middle of the Valdecañas reservoir.
Known as the Dolmen of Guadalperal or “Spanish Stonehenge”, the megalithic monument consists of more than 100 erect granite stones, some reaching 1.8 m high, arranged in a circle 26 m in diameter. It was probably used as a temple, burial ground and even as a place of commerce due to its original strategic location on the banks of the river, and archaeologists believe it was later ransacked by the Romans.
In the 1920s, German researcher Hugo Obermaier conducted an excavation of the site and took a few objects to study and exhibit in Berlin. However, his studies were not published until 1960. Three years later, the area was flooded with the construction of the Valdecañas reservoir, a project to bring water and electricity to the less developed regions of the region. .
The megalithic tombs were submerged during the process. The tips of the tallest stones sometimes appear when water levels drop in summer, but the drought of 2019 was the first time that the “Guadalperal treasure” – as the dolmen is commonly called – became fully visible in almost 60 years.
Its appearance attracted tourists and raised some concerns. Unattended around the dolmen, visitors were left free to touch and potentially damage the megaliths. After decades underwater, porous granite stones began to erode; some cracked and others even fell. This led a group of residents of Peraleda de la Mata, the town where the monument is located, to urge the Spanish government to move the rocks to a safer place to preserve and study.
They created an online petition to save the monument, which drew over 44,000 signatures. But the Spanish ministries of Culture and Sports and the Ecological Transition, as well as a group from the University of Extremadura, have considered the transport of megaliths potentially damaging to the dolmen.
There is currently an effort to declare the dolmen as a property of cultural interest, the maximum protection that a monument can have in Spain. With the return of rain last fall, the water levels in Valdecañas returned to normal and, despite all efforts, the treasure of Guadalperal is back underwater for now.
(Video by Jocelyn Brent; text by Luana Harumi)
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