The Celtic names of hillforts
St. John’s Point
Location: west of Duncansby Head, Caithness
OS map reference: ND 311 751
Celtic name: Birvedunum or Birvedurum
Source: Ptolemy – Virvedrum promontory
This is a coastal promontory fort at the lower end of a slope rising to some 73 metres above sea level, with all of the fort being apparently above the 15 metre contour, so there are cliffs of that height all round the west, north and east sides of the fort.
The first element of the name, Birv, means ‘high hill slope’ and the dun or dur element means ‘summit of hill’, in this case reflecting the fact that the fort is built at the top of cliffs.
The name was transferred to the promontory itself, appearing in the Geography of Ptolemy as the Virvedrum promontory, this form showing the common change of b → v. The presence of the r in the drum ending of Virvedrum suggests that the Celtic form of the name is more likely to have been Birvedurum than Birvedunum.