Moel Offrwm (Upper Hillfort)
Within the Nannau estate near Llanfachreth, there are three hillforts in quite close proximity, Moel Offrwm (Upper fort), Moel Offrwm (Lower fort) and Moel Faner. On the summit of Moel Offrwm hill is the upper hillfort, and it is typically Iron Age in design. The defences are so badly ruined that it has been suggested that they were deliberately destroyed at some time in the past. Inside the fort are the circular impressions left behind from wooden roundhouses (approximately 40), and outside the fort are the remains of an annexe, built against the outer rampart, enclosing an area almost equal to the main fort. It is thought that this was used as an enclosure to protect livestock since there are no visible signs of buildings in this area. This indicates that the fort would have housed a quite large population at one time.