I’ve not yet visited the Great Orme, but according to Gwynedd Archaeological Trust records there’s a prehistoric hut circle north of Pyllau Road (SH77258305). I’ve no idea what kind of access there is to the site, or how much evidence remains on the ground.
There are two other possible hut circles to the south east (one at SH77498300 and the other at SH77358321). One of these looks like it has a public footpath running past it.