The fort was built on a rocky spur giving a superb view over the River Esk in both upper and lower Eskdale, and protecting Hardknott Pass. At an altitude of 800 feet, it isn't the highest fort in the Roman province of Britannia, the highest fort is Epiacum, also in Cumbria. The ruins have been commonly known in recent times as Hardknott Fort or Hardknott Castle, but are identified from the Ravenna Cosmography as the Mediobogdo fort (or more correctly Mediobogdum), situated along the road between the forts of Galava (Ambleside) and Glannoventa (Ravenglass).