The above is from a 1965 booklet titled - Ancient Monuments of Anglesey, published by the Ministry of Public Buildings and Works.
When was the last time you saw a gov't publication with that sort of info in? The book is obviously gonna be useless for transport information now, but the info and diagrams in it are great. Nice plans of the tombs etc. I particularly like the photo of Trefignath before restoration. (Warning: It also covers later Xtian stuff and castles)
Single stone, 8 1/2 feet high, 1/3 mile NW of tregwehelydd farmhouse, admission at any time." I have to find my own bus routes.
And I also have Cadw guide to Ancient Monuments on Anglesey - this is split into driving tours of the island - but does at least have more info on the monuments. it tells you to "ask permission of the farmer, who may help with directions".
sam