Mynydd Mwyn Mawr
I booked this site about 9 months in advance, and was very glad I did, as its very popular, and books up really quickly. This site is amazing, with lovely spacious pitches, each with their own tap, and waste water drain. John (owner) helped with pitching the caravan, as the site is on a bit of a slope. Each pitch has its own leveling block ready for you to use, so very easy to get the van level.
The views are totally amazing, and you may just find that you don't want to leave the site, but just chill and take in the views. The whole of Anglesey is within very easy reach. The local village is only about 1.5miles away and has a small shop for basic provisions, with a big Morrisons and Tesco in Holyhead if you want to do a big shop.
The toilets and showers were lovely and clean, although the floors do slope the wrong way, so you do need to spend a few mins mopping up afterwards, but that's no big deal. The showers were £1 which I thought was very reasonable, considering that would last for at least 20 mins. There's also another separate toilet. There was also a very useful washing machine and freezer. A games room, with free wi-fi was a useful addition, and seemed to be very well used. I did see a review, which said it was dark in the games room, simple answer, put the lights on.
If you have family wanting to visit the area at the same time, but don't want them, or have room for them in your van, then there's a simple answer. Sarah does B&B in the farmhouse, and there's a beautiful static avail for hire (not on CL site, but by the house), the static is a very competitive price, and we are even thinking of using it the next time we visit, instead of dragging the van up from Kent.
The lanes were a bit narrow, but what else would you expect. You can't have a lovely peaceful site, with beautiful views with a main road running along side, so Yes some of the lanes are narrow, but if you follow the instructions, then you shouldn't have a problem.