The Gwynedd Archaeological Trust have undertaken a trial excavation of this hillfort and set up related information boards in Colwyn Bay Library. Their investigations revealed a massive defensive stone wall, well built and faced with good-quality limestone blocks originally rising to about ten feet high. The ramparts were eleven and a half feet thick. These defences are unlike those of Iron Age hillforts but comparable with similar Dark Age fortifications, so may represent a possible stronghold of the Kings of Rhos.