We are staying in Llanberis and plan to drive to Anglesey for the day - is there anything recommended that we don’t miss? We like castles, Neolithic sites and history. Thanks!!
The main castle on Anglesey is Beaumaris Castle, which is also a UNESCO World Heritage Site.
I've heard Plas Newydd is very nice but haven't been myself yet: https://www.nationaltrust.org.uk/visit/wales/plas-newydd-house-and-garden
If you're going to Anglesey and have not otherwise been to Caernarfon Castle then you really should deviate there.
But Beaumaris is the castle you shouldn't miss. See also this recent thread on what else there is to do in Beaumaris- https://community.ricksteves.com/travel-forum/wales/day-trip-from-llandudno-to-beaumaris
For prehistoric stuff on Anglesey see also this thread- https://community.ricksteves.com/travel-forum/wales/prehistoric-sites-near-conwy
[Note- that is by no means an exhaustive list- there are other sites beyond that]
Also the South Stack lighthouse,
and the Copper Kingdom at Amlwch (once the largest copper mine in the world)- https://copperkingdom.co.uk/
And Eglwys Cwyfan (St Cwyfan's Church) at Llangadwaladr, Anglesey, Wales. It is on the small tidal island of Cribinau, it is popularly known as the "Little Church in the Sea". see also https://www.youtube.com/watch?v=fLgAqL1Po_I&list=PLTNGlYhj_wk0V4Wh-zYrBMJp9z-cOh91_&index=4
More a photo opportunity than anything else, go to the town with the long name; Llanfair….gogogoch. Other than the sign, there’s a store and little else. There are plenty of Neolithic sites near it, such as Bryn Celli Ddu Burial Chamber, Bodowyr Burial Chamber, and some standing stones. We visited Penrhos Feiw standing stones and Lligwy Burial chamber when we visited. Another place we enjoyed was Llynon windmill. Other places we visited have already been mentioned.
Where you’re staying I have Ceunant Mawr waterfall and Dolbadarn Castle bookmarked to visit.
There’s an BBC article today titled, “ Doughnut maker 'can't keep up since going viral.” It’s about the owner of the Llynon windmill and how popular his donuts have become. We visited there the day before his pastry shop opened and the pastries were fantastic. We had the pastries and tea after he gave us the keys to windmill and let us wander at will. Since the shop wasn’t technically open, he wouldn’t even accept payment. Based on the article the shop has become very popular.
The donut shop became particularly busy this week because it was visited by a popular American influencer, Kalani, who has been touring Wales. He posts a lot about local food and seems to try and support local small businesses. The donut shop has now made a Kalani donut with a Stetson!
If you have an interest in places to eat in the UK he’s not a bad person to follow.