Gwynedd Archaeological Trust
Regional Historic Environment Record

Henblas Burial Chamber, Llangristiolus

Primary Reference Number (PRN) : 2160
Trust : Gwynedd
Community : Llangristiolus
Unitary authority : Ynys Mon
NGR : SH42577197
Site Type (preferred type first) : Neolithic CHAMBERED TOMB
Status : Scheduled Ancient Monument

Description :
It has long been a question whether the dolmen at Henblas is a natural collection of boulders or a man-made monument. Mr. Edward Greenly in a geological survey of the island inspected the monument and found on the underside of the capstone glacial striae or ice scratching. This in itself would lead to the supposition that the stones had been turned over, but he also observed that these striae did not correspond with the direction of the ice drift, showing that the stone had also been turned round when it was raised to its present position. The group consists of 3 stones: the NE stone is 13ft 6 inches and 50ft in circumference at the base, and the SW stone is 10ft high and 55ft in circumference at the base. The capstone was 13ft by 13ft 9 inches and 4ft thick in places. Two rubble stones wedged in between the edge of the capstone and one of the supporters suggested that it had all been covered over once. A stone 5ft high and 6ft wide once stood four or five paces in front of the SW upright and may have formed part of a gallery. The direct outlook between the two large stones is due east, All three stones are of hard quartzite which occurs in the district. <1>

A group of three very large blocks of stone, two of which are conical and rest on their bases. It is practically certain that the position of the two upright blocks is due to natural causes, but glacial striae on the underside of the third indicate that this has been moved by human agency. Although this group as a whole is mainly natural, it may have been adapted for use as a burial place and it can not be classified until properly examined. (RCAHMW, 1937)

SH 42577197. A group of stones as described, apparently natural although possibly utilised as RCAHM suggested. <3>

Collection of three colossal boulders the largest being 4 x 3.5 x 4.5m high. Two boulders are blocky and one is a very large flat slab leaning on one of the other stones. It is possible that it was once raised up on the other stone as well. A smaller stone beneath southern side could have sheared off the larger rock. In conclusion the two larger stones are almost certainly natural - The capstone is also probably natural although this could have been used to form a chambered tomb. Siting on a slight to moderate hillslope above the Cefni. (Smith, 2003)

Sources :
Smith, G. , 2003 , Prehistoric Funerary and Ritual Monument Survey: West Gwynedd and Anglesey ( © GAT)
Smith, G., and Steele, N. , 2005 , Pan-Wales Prehistoric Funerary and Ritual Sites Survey: Trial Data Synthesis ( © GAT)
The Royal Commission on the Ancient and Historical Monuments of Wales , 1937 , An Inventory of the Ancient Monuments in Anglesey
Neil Baynes, E. , 1910 , Transactions of the Honourable Society of Cymmrodorion , <1>
Ordnance Survey , 1970 , SH47SW 1 , <3>

Events :
40526 : Prehistoric Funerary and Ritual Monument Survey: West Gwynedd/Anglesey (year : 2003)
40527 : Pan-wales Prehistoric Funerary and Ritual Sites Survey: Trial Data Synthesis (year : 2005)

Related PRNs : 302374

Compiled date :


Images :



The above data are supplied by GAT in partnership with its Local Authorities (Anglesey, Conwy and Gwynedd County Councils, and Snowdonia National Park Authority), © GAT 2018 (and in part © Crown, 2018 - as indicated)
This information is supplied for the purposes of personal interest only and may not be used as part of a commercial project.

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