Archaeologists have uncovered evidence of a remarkable prehistoric structure near Stonehenge that may represent the earliest known solstice alignment in the area – predating the famous stone monument's astronomical alignment by around 500 years.

The discovery was made by a team from Wessex Archaeology led by archaeologist Phil Harding.

The site, located near Bulford, dates back approximately 5,000 years and offers new insight into how ancient communities marked the changing seasons long before Stonehenge took its iconic form.

Situated around five kilometres from Stonehenge, the site is contemporary with the monument's earliest phase, when its first earthworks were being constructed. Archaeologists believe it served as an important ceremonial gathering place, attracting large numbers of people for seasonal celebrations.

Excavations carried out as part of the Ministry of Defence's Army Basing Programme revealed extensive evidence of feasting and communal activity, suggesting the site played a central role in religious and social gatherings centred on the summer and winter solstices.

At the heart of the discovery are the remains of two large timber posts that once stood around 120 metres apart. The posts were carefully positioned to create a line of sight towards the rising sun on the summer solstice and the setting sun on the winter solstice.

A reconstruction of the summer solstice celebrations as they might have appeared at Bulford 5000 years ago (Credit: Marijane Porter, Wessex Archaeology)

Although the wooden structure itself has long since disappeared, surviving postholes allowed researchers to investigate its purpose. Analysis by leading skyscape archaeologist Dr Fabio Silva used reconstructions of the ancient landscape, horizon and night sky to confirm the alignment's remarkable accuracy, calculated to within just one degree.

Researchers believe the simple timber monument may have acted as an early ceremonial marker for solstice celebrations before more complex and permanent structures, such as Stonehenge, were developed.

The findings have led archaeologists to suggest that a similar timber alignment may once have existed during Stonehenge's earliest phase, although any evidence would likely have been lost during later construction work at the site.

The discovery provides a fascinating glimpse into the sophisticated astronomical knowledge of Britain's prehistoric communities and highlights the enduring importance of the solstices in the Stonehenge landscape.

Dr Phil Harding, Archaeologist at Wessex Archaeology, who led the excavations, said, “In a few days’ time, Stonehenge will be filled with people celebrating midsummer solstice. But what few will realise is that 5,000 years ago, on a nearby hillside overlooking modern-day Bulford, people were doing the exact same thing – revering and celebrating the sunrise on midsummer’s day. The sun was incredibly important to these prehistoric communities, and they could plot and record its midsummer rising to a high degree of accuracy. 

“This discovery is probably one of the greatest finds of my career, and what makes it so important is just how early it is. Up till now, our knowledge of this ancient feat of astronomy was based on Stonehenge and other monuments of a similar period, but what we’ve discovered at Bulford is 500 years earlier than the famous stones we know so well. It makes me incredibly proud to be an archaeologist."

The original excavations at Bulford, conducted between 2015 and 2017, revealed 48 pits that were radiocarbon dated to around 2950 BC. Artefacts uncovered included pottery, animal bone, worked flints, and charcoal, suggesting that large numbers of people gathered here over a relatively short period of time to celebrate the solar cycle. One of the pits, which may have been part of a ‘viewing station’, contained an extremely rare disc-shaped knife, which was deliberately placed here, possibly as a symbolic reference to the sun disc. 

Dr Matt Leivers, Senior Research Manager at Wessex Archaeology, said, “The discovery at Bulford is fundamental because it’s the earliest example of people building things here that aim directly at the solstice. When we talk about the solstice, we’re talking about religion. About how prehistoric peoples understood the cosmos, the world, and their place in it.

"What we see at Bulford, and later at Stonehenge, is a way of celebrating and marking the passage of time, but it’s also about making sure the world keeps working as it should. It’s likely their way of saying to their deities, please keep us in mind, keep us warm and safe. It’s a religious event. That’s why it’s so important.”