These short shelters alone in the middle of nowhere are actually large stone vats. These buildings in particular are part of the l’Escudelleta Wine Vats in Catalonia, a complex located in Flequer Valley (close to Barcelona).
In Catalonia, at the start of the 19th century, many trees were removed so the land could be converted into vineyards. To avoid logistic problems derived from transporting the grapes to distant villages, they built vats and shelters in the middle of the vineyards.
Nowadays, walking through the forest, these constructions can appear odd and out of place. However, if you compare my photo to the zone drawing I found in an information post, you can get a better idea of the area’s history.
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