I wasn't 100% sure where exactly we were talking about but Iv'e just had a gander at me map, and, no I still havn't been to any of them but have been to the Gelli chamber, it is very nice round there isn't it, the map cuts off on the hill and only one of the sites you mention is on it, Carn Wen, of which there are quite a few of. I did try to take a look at the one near the army land but the ground was on fire...... I shit you not, so I thought it best to move on, I know this isn't very helpful but there you go.