Winter Solstice Report – Newgrange, December 21st 2013

Winter Solstice sunrise shines through the roofbox above the door of Newgrange and along the passage floor

Winter Solstice sunrise shines through the roofbox above the door of Newgrange and along the passage floor

Click the ‘Play’ button below to start a slideshow. You can also click this link  to view larger in a new window, or if you are using a mobile device.

There’s a really special atmosphere at Newgrange on a sunny winter solstice morning, especially so this year since there hadn’t been a clear sunrise here on the 21st of December since 2007. This morning was surely one of the most memorable and welcome sunrises in recent years. Most of the people who had made their way to the ancient passage tomb had come prepared for the worst, it seemed unlikely that the thick cloud and driving rain would ever clear. As dawn approached, however, a clearing to the south west began to spread east, sweeping the horizon ever closer to the point on the opposite ridge where the sun was soon to appear.

The sun finally breaks over the low cloud and lights up the river valley

The sun finally breaks over the low cloud and lights up the river valley

The moment of sunrise passed, a stubborn bank of cloud sat just where the disc of the sun rises above Red Moutain. Within 15 minutes or so the window within which the sunrise can reach the chamber down the long passage would pass and the chamber would remain in darkness. The drumming and chanting from the crowd grew louder and louder, then all of a sudden a dazzling burst of light reached across the river valley, turning the white quartz facade of the 5,000 year old passage tomb a glorious golden orange. Accompanied by a loud cheer, the sun finally stretched across the floor of the chamber within the tomb, much to the delight of the lucky children and adults who had won places to witness the event inside the chamber.

Sunlight bursts through the specially designed roofbox constructed to admit light to reach deep inside the tomb

Sunlight bursts through the specially designed roofbox constructed to admit light to reach deep inside the tomb

The great passage tomb at Newgrange is over 5,000 years old, built in the Neolithic or ‘late stone age’ by local farming communities. For much of that time it had stood in ruin, its passage compressed inwards by the sheer weight of the mound and the ingenious ‘lightbox’ above the door filled in with rubble. It was during the excavations and conservation of the monument from the 1960’s through to the early 1980’s that the secret of its astronomical function was revealed. The phenomenon was first witnessed by the excavator, Prof. Michael O’Kelly of University College Cork, at midwinter of 1967, he described it thus:

‘I was there entirely alone. Not a soul stood even on the road below. When I came into the tomb I knew there was a possibility of seeing the sunrise because the sky had been clear during the morning.’

‘I was literally astounded. The light began as a thin pencil and widened to a band of about 6 in. There was so much light reflected from the floor that I could walk around inside without a lamp and avoid bumping off the stones. It was so bright I could see the roof 20ft above me.

‘I expected to hear a voice, or perhaps feel a cold hand resting on my shoulder, but there was silence. And then, after a few minutes, the shaft of light narrowed as the sun appeared to pass westward across the slit, and total darkness came once more.’

Gathering outside the monument has become a yearly tradition and it’s always great to old faces and new, catch up with the year’s events and look forward to the Christmas holidays and New Year ahead. The staff from the Office of Public Works deserve huge credit for the warm atmosphere and smooth running of the event each year, alongside all the other organisations and volunteers who help keep the event a family friendly affair. It’s great to see the smiling faces of the children emerging from the passage after witnessing something they may remember for the rest of their lives. Having seen their wonderful art hanging in the visitor centre, it was surely a very well deserved prize! Congrats to all the winners of the school art competitions and well done to everyone who took part.

Glendruid Dolmen, County Dublin

Cian (3) and the monstrously large Glendruid Dolmen

Cian (3) and the monstrously large Glendruid Dolmen

Glendruid Dolmen, also known as Brennanstown Dolmen, is one of the finest of the Irish portal tombs. It is also one of the largest examples, its capstone has been estimated to weigh between 40 and 70 tonnes. Although there is no direct dating evidence for this particular portal tomb, it is of a type that were generally built around the early to middle Neolithic period or ‘New Stone Age’ by farming communities that were becoming established throughout the island from about 4,000 BC, replacing the hunter gatherer groups that had first colonised post-glacial Ireland perhaps 4,000 years earlier. This early farming period is characterised by a new tool kit of distinctive stone tools; flint arrow heads, polished stone axes, pottery and so on as well as the introduction of cereals and domesticated animals that became the dominant food source and the basis for a new economy of trade and social exchange.

Situated in a wonderfully secluded valley with a forest walk and fast flowing stream, it is easy to forget that this spectacular tomb is within a short walk of the recently developed Luas tram line through the suburbs of South County Dublin. It is possible to access the valley from the as yet unopened Lehaunstown Luas stop by either climbing a 6ft wall and down a steep bank or by walking along the field south of the station and through a tunnel under the line.

Many visitors remark on the sculptural quality of the tomb, the individual stones have been carefully selected to complement the plan and symmetry of the structure

Many visitors remark on the sculptural quality of the tomb, the individual stones have been carefully selected to complement the plan and symmetry of the structure

Although it seems at first glance that the chamber is quite low under the massive capstone, the ‘legs’ of the dolmen are actually sunken well down into the ground and stepping in over a sill stone to the rear of the monument allows access into a chamber that is really very roomy and comfortable to stand in. It also made a welcome shelter from the passing heavy showers on an otherwise sunny day!

The structural stones lean heavily under the enormous weight of the capstone.

The structural stones lean heavily under the enormous weight of the capstone.

All of the structural stones seem to be of granite. Some lean heavily and have even broken under the stress of supporting such a large capstone. At some point repair and conservation works were carried out to stabilise the structure, a large concrete triangular frame now props up the rear chamber stones and at least one has had large cracks cemented in.

A trip to this wonderful portal tomb makes a great day out, though you may want to pick a dry day as the grassy valley floor can get very muddy. My son Cian, who is three, particularly liked the forest walk and throwing a few sticks into the stream from a lovely little clearing along the banks. 

You can enter the valley via the Luas stop at Lehaunstown by walking along the wide grassy verge from the Carrickmines stop. Do so at your own risk however! There are one or two signs restricting access along the tracks themselves yet there is a small stile inserted into the wall allowing direct access onto the verge, so it’s not very clear whether there is public access to the green areas or not. You will see the dolmen through the trees on the opposite side of the stream along the forest path. You can try and cross the stream at a tricky looking fording point close to the tomb or continue along the path until you reach an old stone bridge and walk back along the valley bank. Alternatively there is direct access from Brennanstown Rd. through the grounds of a private house.

Click on a photo to open the gallery viewer:

More information and pictures of Glendruid available on: Megalithomania, Megalithic Ireland, Megalithic Monuments of Ireland

Equinox Dawn, Loughcrew, September 2012

Equinox Dawn, September 22nd, 2012, looking east past Patrickstown Hill towards Slane where the sun rises over the Irish Sea.

For three days around the Equinox, which occurs roughly around the 21st March and September each year, the Office of Public Works allow access to the chamber of Carin T, the central passage tomb on Carnbane East, Loughcrew, Co. Meath. Cairn T is also the largest on this central hill of a small chain of hills which are conspicuous from many miles around due to the low lying farming land in this part of the country. Within its passage and chamber, the passage tomb is highly decorated with a type of carving described as megalithic art, made by chipping away the surface of the stones that make up the structure that sits underneath a massive cairn or stones.The passage tombs on Carnbane East have not been scientifically excavated though the style of construction and decoration suggests that they are probably contemporary with, or even earlier, than the great passage tombs of the Boyne Valley at Newgrange, Knowth and Dowth. Knowth and Newgrange have produced radiocarbon dates from the late neolithic for the main construction phase, indicating the main focus of passage tomb activity dates back to around 5,000 years ago.

Catching the sunlight on the backstone of the rear chamber of the passage tomb

The weather reports for the weekend suggested that the morning of the actual astronomical Equinox, the 22nd, would be the best chance to see some light inside the chamber. Although there were clear skies when I left Wicklow at just before 5am, as I travelled north the cloud began to build over the eastern horizon. Though a large cloudbank above the clear horizon can lead to some spectacular colours, it did also limit the amount of time the sun would shine inside the chamber. On a clear morning the Fsun may be visible in the back chamber for almost a full hour, on this morning we had a much smaller window of about 20 minutes. As the event has become publicised more widely, so the crowds have grown larger each year. This September there was a crowd of about 150 people qeueing from before dawn, since the chamber can only accomodate six or seven people, inevitably only a lucky few would see the full display of light.

Megalithic Art Illuminated by the Dawn Sunlight

Click  the ‘play’ button on the slideshow below to view a selection of photos from the equinox event or click here to view a larger version of the slideshow on the website, should also work on the iPhone/iPad and other mobile devices.

Laser Scanning the Great Tombs of the Boyne Valley

Marcus sets up the instrument to begin a 360° scan of the chamber and passage of Knowth East, collecting an astonishing 500,000 data points approx. per second.

As one of Ireland’s foremost heritage landscapes, the great neolithic passage tomb complexes of Newgrange, Knowth and Dowth, collectively known as Brú na Boinne, attract hundreds of thousands of visitors every year. The chamber within Newgrange, the most famous of Ireland’s many passage tombs, welcomes a steady stream of tourists who crouch and shuffle single file up the long passage, literally rubbing shoulders with some of the finest megalithic art in Western Europe.

In the 5,000 or so years since it was first constructed, the settling of the mound’s layered bulk had caused many of the uprights lining the passage to lean and tilt inwards, making parts of the passage difficult to negotiate. This was remedied during the excavations and renovations led by Prof. Michael J. O’Kelly between 1962 and 1975 so that today the chamber is readily accessible. At Knowth and Dowth however, the chambers remain largely out of reach for most visitors due to a mixture of structural obstacles, site management and safety concerns.

At Knowth East, the passage orthostats nearest the chamber lean in so heavily that the only route through is on hands and knees along a wooden plank. At the time of the chambers discovery in 1967, the excavator, Prof. George Eogan, actually entered by crawling above the passage orthostats, eventually managing  to reach the chamber floor below by lowering himself down along the two metre high portal stones.

The situation is not much different at Dowth North, here the only means of access to the passage is a rather claustrophobic and uncomfortable crawl down a 20 metre long souterrain that was probably constructed between the 9th-11th centuries A.D. The lighting fixtures that had been installed decades ago are now flooded and defunct, the chamber now lies in damp and eerie silence.

With the sophisticated technology and expertise offered by a team from the York Archaeological Trust however, it is hoped that ‘virtual visits’ may be offered in the future through the medium of 3D virtual reconstructions and interactive ‘fly through’ videos of these unique and remarkable sites. The incredible level of detail and realisitic textures captured in this project will also allow researchers, whether within Ireland or abroad, to continue to study and analyse the construction and decoration of the tombs from their desks.

Over several days in May 2012, Dr. David Strange-Walker and Marcus Abbott meticulously scanned, photographed and logged GPS co-ordinates for both Knowth and Dowth in an exciting project organised in conjunction with UCD. Dr. Steve Davis of the School of Archaeology in UCD was one of the main co-ordinators of the project and both he and David were interviewed inside the chamber of Knowth for a piece on RTÉ News, broadcast on the 15th May:

Phillip Bromwell of RTÉ meets the team at Knowth.

I was delighted to be given the opportunity to meet the team and check out the work going on within the chambers of Knowth and Dowth and am very much looking forward to seeing the results of the surveys and scans, particularly the megalithic art. Having firsthand experience of how difficult it can be to record and in some cases even access the sheer number of decorated stones, it will be very interesting to see how technological advances along with the talent of people like Marcus and David can bring this collection of some of Europe’s finest pre-historic carvings to life for everyone to enjoy.

In the meantime, below are some images from my short visits to see the team in action. This was of course a very challenging environment to work in. Not only are there extremely low light levels within the chambers, but due to the scale of  the project it was not exactly practical to stop the work in progress and set up some atmospheric environmental portraits, not to mention the need to regularly find the nearest hiding place and sit still for several minutes while the scanner was collecting data! All of the shots therefore were taken handheld at exceptionally low shutter speeds mostly combined with very high ISO settings to increase the sensitivity of the camera just to avoid blurring as Marcus and David went about their various tasks.

Marcus secures the scanner to its low-level base where the passage meets the chamber in Knowth East.

It’s very much a case of ‘watch your head’ and ‘watch your step’ in the eastern chamber at Knowth.

Marcus checks the location and visibility of the targets which will allow the different scans to be combined later with sophisticated software.

The large basin stone in the rear chamber, Knowth East.

Marcus checks the settings on the scanner before it begins a 360° scan of the chamber and passage.

David Walker sets up the camera to capture the texture and colour of the surfaces that have been measured by the laser scanner.

The scanner set up in the right hand recess of the main chamber of Dowth’s northern passage.

The chamber in Dowth North is normally in permanent total darkness, the lighting arrangements are ‘bring your own’.

The very talented Marcus Abbott (left) and David Strange-Walker pictured in the eastern chamber of Knowth.

For more information on laser scanning and past projects using similar techniques, the wonderful website of the Nottingham Caves Survey project is very much worth a browse. Other exceptional case studies are featured on Marcus Abbott’s site. Special thanks are due to Dr. Steve Davis for arranging access for both myself and the team over the ten day period and particularly to the OPW for their time and co-operation in facilitating the work.