Future avocado farm in Spain turns out to be major megalithic site: “not common and truly unique”

Researchers discovered 526 menhirs, or standing stones, from between the sixth and third millennia BC on the hill and its surroundings. Image: Linares-Catela et al./ Trabajos de Prehistoria (CC-BY 4.0)

Bad news for an aspiring avocado farmer in the Spanish province of Huelva. During a standard survey of the intended farmland in 2018, archaeologists stumbled across one of the largest Neolithic standing stone complexes in Europe. A recently published study shows that the oldest upright stones could be up to 7,500 years old, while the entire complex features thousands of stones that were used for different purposes.

Some of the largest stones stand on their own, but others were used to build tombs, mounds, stone circles, enclosures and linear rows. The diversity of the structures turns out to be a huge puzzle for researchers. “This pattern is not common in the Iberian Peninsula and is truly unique”, explained José Antonio Linares-Catela, a geoarchaeologist at Huelva University and lead author of the study that was published in the Spanish journal Trabajos de Prehistoria. “This is the biggest and most diverse collection of standing stones grouped together in the Iberian peninsula. A major megalithic site in Europe.”

His colleague, Primitiva Bueno-Ramírez, professor of prehistory at the University of Alcalá de Henares (near Madrid) confirmed to El País that “to date, no such compact concentration of megalithic sites is known, with such expectations of obtaining archaeological data, anywhere in Europe.” She stressed that, since both universities of Huelva and Alcalá plan to fund research at least until 2026, local councils and mayors in the region, as well as the owners of the land, should be involved in the process.

Rumour has it

The team of archaeologists suspect that the earliest stones on the site were erected around 7500 years ago. The latest ‘megaliths’ – the ancient Greek word for “great stone” – date from the second millennium BC, some 3000 to 4000 thousand years ago.

Despite the large scale of the megalithic complex, researchers were not completely surprised about their findings. Local folk tales spoke about menhirs that once stood at the site, called La Torre-La Janera. The archaeological survey conducted in 2018 showed that there were traces of Neolithic standing stones. But it was only recently that discovered the true size of the New Stone Age complex, Linares-Catela told Live Science.

The hilltop at La Torre-La Janera could be one of the most complex Neolithic sites ever found in Europe.
Image: Linares-Catela et al./ Trabajos de Prehistoria (CC-BY 4.0)

Additionally, the site of La Torre-La Janera itself is an interesting place to start digging. While it is now located on the left bank of the Guadiana River, about 15 kilometres from the coastline, this was not always the case. Around 6,500 and 4,000 years ago, the sea level was two meters higher, meaning the site would have been far closer to the shore than it is nowadays.

Prehistoric diversity

One of the most interesting things about the discovery was finding such diverse megaliths in one location, according to Bueno-Ramírez. They were also surprisingly well preserved, she told The Guardian. “Finding alignments and dolmens on one site is not very common. Here you find everything all together”, she referred to the linear arrangements of stones (alignment), stone circles (cromlech) and dolmens (tombs made of two standings with a flat capstone on top).

Apart from the 562 excavated standing stones, archaeologists found numerous burial grounds at the site. Some have funerary containers, while others may have played a role in commemoration rituals. The stone-encased burial grounds have different lengths, ranging between 6 and 17 meters. In addition, 41 stone coffins built to hold two or more bodies have been documented in the study.

One of the many dolmens excavated at the site. Experts suspect there are many more to be found.
Image: Linares-Catela et al./ Trabajos de Prehistoria, CC-BY 4.0

It appears that the Neolithic site was important for the prehistoric society that used it. The archaeological report suggests that La Torre-La Janera could have been used to observe the cycle of the seasons or astronomical events since the monuments were erected in specific locations, with wide visibility of the landscape. These structures were connected spatially with the surrounding land, horizon and sky according to the report. “They are generally oriented to the solstices and equinoxes, but there are also solar orientations in the alignments and the cromlechs”, Bueno-Ramírez said.

Unravelling the details of La Torre-La Janera might take a while, as many of the stones are buried deep in the earth. They will need to be carefully excavated at least until 2026, but “between this year’s campaign and the start of next year’s, there will be a part of the site that can be visited”, Bueno-Ramírez said.

Sources: El País, Live Science, The Guardian, Trabajos de Prehistoria (Spanish)

This article was originally published in English. Texts in other languages are AI-translated. To change language: go to the main menu above.