The Gwynedd Archaelogical Trust have identified a hut circle located.... well..... exquisitely upon the northern flank of Trum y Ddysgl (The 'Ridge of the Dish') a summit of the wondrous Nantlle Ridge (in the interests of objectivety, note that I am somewhat biased here.... ). The site lies quite a way below the airy 2,329ft summit, so needless to say requires quite a diversion. I haven't made this myself, (to be fair) the result of ignorance rather than neglect of duty. But what an unbelievable, utterly extreme place to live! The mind truly reels at the very thought of it. Right on! The relevant GAT PRN is 6607:
'A hut circle, c.11m in diameter, located on a small ridge with excellent views eastwards along the Nantlle Valley. The site consists of low (0.3m high) wide stony banks, no entrance is visible although the site is partly obscured by rushes. The remains of a possible enclosure wall runs off from the hut circle to the SE. At the SE end of this there may be a small sub-rectangular feature (c.2m x 2m). There are two post-medieval drainage ditches, one just below the hut and one above it'
Source: Jones, S., 1996
Note that an ascent via Y Garn to the east would engender a visit to two very substantial Bronze Age cairns en route... as well as much else. But please... please.... take great care when negotiating the crags of Mynydd Drws-y-Coed.