['< full sod > according to [ [ radiocarbon dating ] ] as conducted in connection with an archaeological excavation in may the summer of 2007, the nan ringfort mostly dates from the extremely early 10th to mid - 12th century. later occupation deposits nearby indicate the fort was used from around the early 10th century to the early 13th century. around the somewhat later structure a with a rectangular outline structure was likely built between the early 15th and mid - 17th century. < ref name = " report " / > { { rp | 28 } } < eod > < sod > nan < eod >']