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Bryn Celli Ddu Burial Chamber

nr Llanfair Pwllgwyngyll, Anglesey

Location Guide

The entrance now

Bryn Celli Ddu is a prehistoric site on the Welsh island of Anglesey located near Llanddaniel Fab. It was at one time a stone circle in a henge, replaced later by a larger impressive structure, and has a wealth of features to see.

This is a site where over a very long time, many items, or monuments have stood, and is unusual in that the later item was placed over the earlier one, is in the opposite developments sequence thought to apply to these different forms.

Historically this was both a very impressive and important site, that is now often overlooked and as far as I am aware very little recent work has been done. Very little of the area around has been investigated.

The earlier item that we understand was on this site, was a henge with stone circle, this was later destroyed and replaced with what is thought to be a passage grave. The passage in the later item lines up with the summer solstice, and light foods down the entrance for around 20 minutes, for a few days either side of the summer solstice, this is the same as at NewGrange in Ireland. Prior to the henge something stood here.

In addition to this there are stones with carvings and a pit that had a display built from Ox bones, plus another stone covering a small pit containing human remains. It is suggested that the Ox bone feature is similar to another found in France and this has been connected with fertility rites connected with breading the captive heard of oxen.

The name translates either as 'the mound in the dark grove' or possibly 'the mound in the grove of the deity'. This may suggest later use by Druids, known to be in this area.

The rear now with copy stone,
the mound when built would have come out to the ditch shown

Postholes and Stones - 4000BC or Earlier

It is likely that something, now not understood, perhaps covered in part by the henge, was on this site earlier than we have details here. The basis for this is that a row of five postholes near the entrance previously thought to have been contemporary with the tomb (c. 3000BC) have recently been proved to be much earlier. Early results from a radiocarbon programme dated pine charcoal from two of the pits to the Mesolithic (Pitts, 2006), far earlier than the henge.

Artists impression of henge and stone circle

The Henge - around 3000BC

Henges are found mostly in England and Scotland, with examples in Wales and Ireland being rare, they are not found elsewhere in Europe. A Henge is a roughly circular area ringed by a ditch which is in turn, encircled by a bank. The bank and ditch are usually broken by one or more causeways giving access to the central area which often contained structures made of wood or stone, such as a stone circle.

Henge monuments like this only start to appear in Britain towards the end of the Middle Neolithic period, while the the passage graves are from earlier than this usually.

Henges come in all sizes, the one here is quite small compared to many others. In this case it was a henge with a central area about 20m across (diameter), and this was surrounded by a 2m deep flat bottomed ditch that was about 5m wide. Another account gives the ditch as 69m (21ft) in diameter, 5.2m (17ft) wide and 1.8m (6ft) deep. Outside this, would have been a bank, but no remains exist of this, possibly partly through robbing to build the later monument and through many years of agricultural use of the land.

The henge, that contained a central stone circle, not completely round 17m by 20m, it was a full ring. Evidence exists of 14 large stones and there is a gap at the east which probably contained 3 more. It is unclear whether the eastern gap is original, or a consequence of the construction of the Passage Grave. The stones are arranged so that lines through opposing pairs all intersect at the same point in the centre of the Henge, this fact and other finds we cover below, suggests that there may have also been a central construction of some kind, perhaps an alter.

Small amounts of burnt bone and shattered quartz had been buried at the foot of some of the circle stones, and two of the stones each had the complete cremation of a young girl buried at their bases.

No evidence of causeways have been found, and the ditch was only explored to a small extent during the excavations of 1928, and the most likely location for the causeway, at the east, is partially buried under the passage and forecourt area of the later tomb.

The Henge was in use for a considerable time before its destruction, long enough for its ditch to partially silt up, and for grass growth to build a deep organic layer on the ground surface.

The Pit and Decorated Stone

Some time after the Henge was built, but before the construction of the Passage Grave, a pit was dug at the circle centre. About a metre in diameter and about 1.5m deep. A burnt human ear bone and wood were found at the bottom of the pit.

After use, the pit had been filled in and covered with a flat stone, alongside this cover stone was another large stone with carved decoration. These finds, and the alignment of the stone circle suggests that there was probably a central construction of some kind in the henge, perhaps an alter.

The carved stone was decorated on both sides, suggesting that it was meant to stand upright, and a replica of this stone has been erected near to the site of the pit. The original having gone to the Museum of Wales.

The decorations on this stone was long sinuous lines which pass over what is now the top of the stone from each side. The carvings on one side have a kind of maze structure and incorporate a spiral, the opposite side carvings have a more zig-zag appearance. The style of the carvings are said to be similar to the carvings at Barclodiad y Gawres Burial Chamber and to carvings found in some Irish Passage Graves.

If this stone were originally free standing, it would be the first of itís kind to be found in the British Isles.

This decorated stone was buried, if it had been erect at the centre when the stone circle was savaged, it would probably have been destroyed, but it appears to be the full stone. The reason behind the pit digging and the stone burial is not understood.

Stone up close

Round unconnected pillar inside

 Close up of stone

The Passage Grave - around 2000BC

Next we have what time wise we would have expected to have occurred first, the building of a passage grave. Passage Graves are thought of as early monuments, yet this one must have been built in the Late Neolithic period, however this may not be what it appears to be. In that, like Newgrange in Ireland, there is a lightbox effect where light travels down a long entrance tunnel for a few days either side or the summer equinox at sunrise for around 20 minutes a day illuminating the central chamber. In the back of the chamber is a quartz rich stone that lights up when the sun strikes it.

To construct this, the stone circle shows evidence of intentional destruction, 5 stones were removed, 2 toppled, 1 buried, and 6 broken. Excavation revealed that the broken stones had been toppled and then smashed by the dropping of heavy stones on them, all of the stones, except one, were intentionally damaged before being buried beneath the cairn. It is suggested that this deliberate destruction shows a strong dislike of the beliefs that the stones represented, especially as it would have been much less effort to reuse the stones in the passage grave structure. However we do not know that the destruction of the stone circle was at the hands of the cairn builders. It might for example have been some other raiders who visited, destroyed the shrine and the locals then pushed them out, and rebuilt it as a cairn based on another design they knew better.

The Passage Grave was mush larger and impressive than it is now. It was more than twice its current size, made up of a large cairn that completely buried the central area of the Henge, the much smaller cairn that can be seen today is a modern construction.

I assume it was largely destroyed in the archaeological excavation between 1928 and 1929. It had previously  been plundered in 1699.

Originally it was 27m in diameter and had a double kerb, or two stone rings, which was set at the bottom of the Henge ditch, so the ditch that is visible today is only half the width of the original. The kerbs were inter-filled with dry stone walling, this was also continued above the kerbs to stabilise the cairn structure.

Although double, only the outer ring of kerbs was visible for much of the circumference, the inner ring only emerging from under the cairn in the arc containing the passage entrance. While the outer kerb was used to form the walls of the passage, the inner kerbs sweep back above the outer passage walls up to the portal stones where they form a wall to retain the cairn material in this area.

If you visualise this you will see it would, with the stonework catching the sun, be outstanding.

The entire passage is about 8.5m long and about 1m wide. The first 5m was roofed, the outer 3.5m was open, this division is marked by two large portal stones which originally had a lintel.

Inside the passage are two unusual features, a low bench or shelf is incorporated into the north wall, and in the south wall are two niches in which there are two tiny standing stones. The significance of these is unknown. The small stones appear to be small versions of the fallen circle stones.

Looking in (flash fill)

Looking Out (natural light)

The chamber is polygonal, about 2m wide, and constructed from six large side slabs and roofed with two large capstones.

A large pillar stands in the northern corner, reaching almost to the roof. The surface of this stone has been worked to give it an almost circular section.  Free standing stones in burial chambers are very rare and a shaped pillar like this is probably unique. A striking but not understood feature.

There is a carving on the southeast wall slab about 1m above the present floor level. The carving seems to be in the form of a spiral, but this is far poorer than rock art found on the external carved stone. Some suggest this as not an original feature.

Entrance now


The sealing of the Passage Grave

Given that the monuments is constructed with the ability for the sun to shine through the entrance and illuminate the central chamber on a specific date, it was not initially intended to have been sealed and its fair to assume that it's use changed again, when the blocking occurred. It may be that before the blocking it was not a grave, but after it was.

The tomb had been sealed by the blocking of the outer passage with stones, earth and cremated bone.

The inner passage was not blocked and the division was marked by the inclusion of a row of quartz boulders on the inner edge of the blocking material.

The forecourt area at the entrance to the outer passage seems to have been the focus for ritual activity, fires had been burned here and a small platform of white quartz pebbles had been laid. Platforms of this kind have been discovered outside several Irish Passage Graves such as the one at Newgrange.

Finally, on the blocking of the outer passage, the forecourt area was covered with fan shaped layers of stones radiating out for 2-3m from the entrance.

Further from the entrance, beyond the ditch, were found the bones of a young Ox surrounded by a three sided construction of upright stones and post holes. It is not clear to which of the monuments this feature belongs. The post holes we know now belong to something at predates all we can see toady.

A similar pattern of ox bones have been found in a site in France and was there thought to be connected with fertility ritual for their Ox herds.

What we see now

An earth barrow covering the grave is a twentieth century restoration, that has little in appearance similar to the original its simpler, plainer and sits inside a ditch of half the original width. The arrangement of the chamber and light entry remains unchanged and the sun still illuminates the central chamber for around 20 minutes at sunrise each day near to the mid summer solstice. If you were to imagine the stones on display around the mound as part of the inner of the two rings, and the stones you see in the ditch as the other rings of stones with a large mound filing up between you get an idea of the scale of the original.

Other background Information

Norman Lockyer, in 1906 published the first systematic study of megalithic astronomy, and was the first to suggest that Bryn Celli Ddu marked the summer solstice. This was ridiculed at the time, but recent research by Steve Burrow, curator of Neolithic Archaeology at Amgueddfa Cymru (National Museum of Wales) has proven his theory to be true. This alignment links Bryn Celli Ddu to a handful of other sites, including Maes Howe  at Stegness, Orkney and Newgrange in Ireland, both of which point to the midwinter solstice. It has also been suggested that a feature similar to the 'lightbox' at Newgrange may be matched at Bryn Celli Ddu (Pitts, 2006).

"It's stunning", he says. "First there is a sparkle through the trees, then the sun rises out, it's quite exhilarating". The rays light up a quartz-rich stone at the back of the tomb."

Location: Bryn Celli Ddu Burial Chamber, nr Llanfair Pwllgwyngyll, Anglesey

Grid Reference: SH508702 Ceremonial County: Anglesey

Map Link: Get-A-Map Multimap   maps

Aerial photo: Multimap

Getting there: From A55 once over the Britannia Bridge take first exit to Llanfair Pwllgwyngyll and then left onto the A4080 to Brynsiencyn. After the entrance to Plas Newydd at the next crossroads take the minor road on the right to Llanddaniel Fab. Halfway along this road there is a parking pull in on the left hand side.

Access: From the car park pull in cross the road and cross the stone stile beside the bridge onto the fenced footpath for 700 yards, which takes you a long the side of fields at the point where a stile takes you right, go left over the footbridge which crosses the stream, continue to follow the fenced footpath past some houses and round to the left. On the right hand side you come to a gateway that takes you into the site.
Website: CADW    Visit Anglesey

Other Useful Websites: Wikipedia  Geograph   Megalithic Megalithic.co.uk  

Pegasus archive   information on quartz rich stone discovery

Postcode: Telephone:
Opening Times: Open all the time


Nearby Locations: Plas Newydd  
Other Location Pages: Maes Howe  
Other Relevant Pages: Anglesey Attractions   Anglesey Attractions Map

Notes: A torch would be useful at this site to go down the passage, however at the end there is natural daylight in the circular chamber.

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By: Keith Park Section: Heritage Section Key:
Page Ref: Bryn_Celli_Ddu Topic: Burial Chambers and Mounds  Last Updated: 07/2010


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