New Discoveries about Britain’s Stone Circles

We’ve written about Britain’s prehistoric stone circles before, but recent studies from 2017 to 2019 show there are likely more secrets to uncover about these Neolithic monuments. In this post we will look at the latest news and discoveries about the prehistoric stone circles in Britain, including its most famous icon, the Stonehenge.

Click through to read our previous articles:

• Exploring Britain’s Neolithic Past
• Neolithic Burial Chambers: Telescopes to the Stars
• Standing Stones in Prehistoric Britain

If you’re interested in knowing more about Britain’s fascinating ancient stone monuments and exploring prehistoric stone circles with like-minded people, consider joining us on a small group tour. Odyssey Traveller visits a number of these prehistoric sites in England, Scotland, Wales, and Northern Ireland. In our small group tour focused on Prehistoric Britain, for example, we take a scenic drive through England and the Scottish Highlands and visit several Neolithic Sites including the Uffington White Horse and the inspiring Stonehenge. A local guide will also join us on a day tour to take us across the Cotswolds for a morning stroll and visit to Rollright Stones.

In Walking Rural Britain, we experience the beautiful white cliffs on the coast of Dover, the scenery giving us much to think about ancient British history and culture. We take a walk with our local guide through country lanes, wandering through rural towns and its thatched cottages to be inspired by the local beauty and hear the legends of people who first settled in the area.

Click through the links to see the highlights and hidden gems included on our tours.

A Square Inside a Stone Circle

In 2017, a research team led by the University of Leicester and University of Southampton with archaeologists from Britain’s National Trust made a startling discovery: the Avebury stone circle in Wiltshire contained a square.

The prehistoric Avebury henge dates back to the Neolithic (New Stone Age). A “henge” is the name for a circular Neolithic earthwork consisting of a bank with an internal ditch found on the British Isles. Not all henges have standing stones, but Avebury does, a large outer stone circle with two smaller inner circles inside it.  Its outer circle is the largest stone circle in Europe, 330 metres across and originally having 100 standing stones.

Now researchers have found a “unique square megalithic monument within the Avebury circles”, likely the earliest built structure on the site, surrounding a single upright structure known simply as the “Obelisk” back in the 18th century.

Stone circles, like the famous Stonehenge, are well-known structures from the Neolithic era; stone squares much less so. The team’s research continues, but they are hopeful the discovery of the unusual square monument is key to understanding why the Avebury henge was built where it was.

Origins of Britain’s Stone Circles

Finding out why these megalithic stone structures were built by our ancestors has preoccupied historians and archaeologists for centuries–mainly because it is a research question that’s difficult to categorically answer.

It is unknown where the very first stone circle was built (Aubrey Burl, Prehistoric Stone Circles [4th ed.], Shire Publications, 2010). Though they share similar architectural features, stone circles also display such great variation that a modern recreation has even fooled archaeologists: in January 2019, a Scottish council announced that a previously unknown stone circle dating back 4,500 years has been found on a local farm, only to discover that the “Neolithic” monument was constructed by a farmer in the 1990s. According to Jason Daley, writing for Smithsonian.com:

Neil Ackerman, the Historic Environment Record Assistant working on the project, says in a press release that the site’s completeness, smaller stones and small diameter were unusual, but didn’t cause major red flags as there can be a huge amount of variation between the stone circles. Also, there is no reliable method to date exactly when a stone was planted in the ground.

These Neolithic monuments were not confined to the British Isles. Gobekli Tepe in southeastern Turkey predates Stonehenge by 6,000 years. Its tallest pillar stands around 5 metres (16 feet) and weigh between seven and ten tonnes. Also predating the British structures were the standing stones of Nabta Playa in southern Egypt, erected 7,000 years ago.

Scientists say the stone circle of Nabta Playa served as an astronomical device to mark the summer solstice, associated with summer rains, as well as the arrangement of stars, used in navigation. The stone circle measures only four metres in diameter, with stones including four pairs of large stones. A survey in the late 1990s using global positioning satellite revealed that one of the pairs aligns to form a north-south line, while the other pair forms an east-west line, providing a line of sight toward the summer solstice horizon of 6,000 years ago, and marking the spot where the sun would have risen and set.

Domestic debris was found on the site–hearths, animal bones, pottery shards. “The nomadic groups must have engaged in a variety of activities during summer occupation, such as social bonding, marriage, trade and ritual,” the authors note, cited in Scientific American.

Professor Alex Bayliss, who has studied the stone circles on the Orkney Islands, came to the same conclusion in 2017. She claims that Neolithic communities did not live at sites, used them as a gathering place for festivals and to meet a partner.

Orkney’s Standing Stones of Stenness, as well as the Callanish Stones on the Isle of Lewis, were believed to be constructed with astronomical phenomena in mind–like Nabta Playa.

[T]he arrangement of the stones in the two locations is so precise that they can even be used to measure the moon’s appearance at its most northerly position on the horizon – an event which only takes place every 18.6 years. (Source.)

The 2016 study regarding Stenness and Callanish was based on the 1955 findings of an academic called Alexander Thom, who studied Britain’s standing stones starting in the 1930s and theorised that they served as observatories.

A recent study, reported in February 2019, says “the placement of the sites suggests the concept of megaliths spread over sea routes originating from northwest France”, as researchers found that the earliest predecessors of the European sites were seen in that area, particularly in the Paris Basin (between 5061 to 4858 BC) and later emerged in the coastal areas of the Iberian Peninsula and the rest of Europe. Stonehenge is located away from the coast, but researchers note it was also built near the end of the megalithic age (stone circle construction appeared to have stopped around the Bronze Age, 1500 BC), giving time for the concept to spread from coastal areas.

Passage Tombs, Boulder-Circles, and Monoliths

As of 2010, there are more than a thousand stone circles still in existence in the British Isles, though many have been damaged (Burl, 2010, p. 11). Other megalithic structures, such as passage tombs and boulder-circles, have also been discovered and preserved.

A passage tomb is a mound structure with a passage into the centre, leading to one or more burial chambers. Boulder-circles, as described by Burl, are open rings of boulders enclosing burial cairns, which look like bicycle wheels if viewed from above.

In the British Isles, the oldest megalithic structures may have been erected in northwest Ireland. In 2018, archaeologists found a 5,500-year-old passage tomb at Dowth Hall in the Brú na Bóinne World Heritage site, the most significant archaeological discovery in Ireland in the past 50 years. The tomb, 40 metres in diameter, may have been one of the earliest tombs constructed in the area.

On the Cúil Irra peninsula near Sligo, Ireland is Carrowmore, a large group of megalithic tombs made up of several tombs surrounding its largest monument (called Listoghil, erected around 3500 BC) on the high point of the plateau. Thirty monuments remain, the rest lost to time and to quarrying activities in recent centuries. Many boulder-circles survived but without the tombs they protected. One of the boulder circles, Burl reports (2010, p. 16), is in the suburbs of Slingo, Christianised with a statue of the Virgin Mary and converted into a traffic island.

There are also isolated monoliths whose intended purpose we can no longer be sure of.  “Long Meg“, standing apart from her “Daughters” standing in a circle in Cumbria, stands nearly four metres (12 feet) tall, decorated with spiral carvings. Long Meg could have been used to track celestial events, but other monoliths were too short to be useful in observing the heavens. So what were they for? We can only guess.

The Obelisk of Avebury survived long enough to be recorded in the 18th century (it was said to have stood six metres, or 21 feet, taller than Long Meg) but was soon broken up and used as building material.

Stonehenge and the bluestones from Wales

The Stonehenge may just be the most famous megalithic monument in the world and the most iconic landmark in Britain. The monument shares similarities with other stone circles in Britain; what makes it unique are its sarsen stones arranged in a post-and-lintel formation (two posts holding up a third, laid horizontally on top of the two), and its smaller “bluestones” found to have come all the way from Wales.

Stonehenge was built in stages. The oldest part of the monument was built around 3000 BC. The bluestone pillars came first, followed by the huge sarsen stones about 500 years later. Most of the surviving 45 original bluestones of Stonehenge are of spotted dolerite found to have originated from the Preseli Hills of southwest Wales.

Some were as long as three metres (10 feet) and weighed four tonnes; a popular theory said they were transported by sea. A new study reported in February 2019 now debunks this theory, suggesting that the stones were transported by land.

The researchers led by University College London pinpointed two quarries in Preseli Hills where the Stonehenge bluestones likely came from. As the quarries were in the north side of the hills, the Stonehenge builders could have just made an overland journey from there to the Salisbury Plain.

The team continues to investigate to find out what’s so special about the Preseli Hills that the builders had to travel 290 kilometres (180 miles) to get building material 5,000 years ago. The study suggests it may have been because the pillars were “relatively easy” to remove as they were natural vertical pillars that could be chiselled away.

Stonehenge Speculations

Investigation of Stonehenge dates back to the 17th century. Antiquarian John Aubrey and archaeologist William Stukeley both believed Stonehenge to be a Druid temple in Celtic culture, however we know now that Stonehenge predated the Celts by about two millennia.

There were many competing theories as to why Stonehenge was built. Modern theories say it is either a place of ritual or a scientific observatory. A more recent theory, first floated in 2008, said the Stonehenge could have been a place of healing, based on Bronze Age skeletons with bone deformities found in the area, like the Amesbury Archer, a skeleton with a knee injury.

The ancient Britons who built the Stonehenge and the other stone circles in Britain did not leave written accounts of their reasons and technique, and so the speculations continue.

Summer Solstice at Stonehenge

Despite the fact that Aubrey’s Druid theory has been rejected by modern scholars, this megalithic monument on Salisbury Plain still attracts members of modern-day Druidic societies (who have claimed Stonehenge as their temple) and curious travellers every year on Midsummer Day, to mark the summer solstice. On June 21, 2018, over 9,000 people flocked to Stonehenge to watch the sun rise behind the Heel Stone, the entrance to the monument, and celebrate the longest day of the year, erupting in cheers as the sun rose at 4:52 AM.

You can watch a video below about the Stonehenge celebrations from CNN.

If you want to see more of the British Isles, join Odyssey Traveller’s Prehistoric Britain History Tour, which visits the sites of many of Britain’s most iconic standing stones. You may also consider the Walking Rural Britain Tour or the Scottish small group tour. For more tours in Britain, click here. All of these tours are especially designed for senior travellers.

Originally published March 3, 2019.

Updated on October 15, 2019 and then September 23rd 2021.