Celtic toponymy from Brythonic *"crüg" 'hill' (Irish "cruach") From tribal name "Dumnonii" or "Dumnones", from Celtic *"dumno-" 'deep', 'world' From Celtic *"dubr-" 'water', *"dubrās" 'waters' (Welsh "dwfr"; Breton "dour") First element is possibly "dun", ' hill fort' (Welsh ddin, 'fort'). First element from Celtic *"duro-" 'fort'; in "Dūrobrīvae", Celtic *"brīwa" 'bridge' Possibly derived from Brythonic *"iska", 'water, fish' and *"leith", 'damp, wet'. From Celtic *"iska" 'water' (Irish "uisce"); second element in "Isca Dumnoniorum" (Exeter) is a tribal name (see "Devon") From Brythonic *"lēd-" [from Celtic *"leito-"] + *"rïd-" [from Celtic *"(φ)ritu-"] = "Grey Ford" From Celtic *"lindo-" 'pool' + Latin "colonia" 'colony'
Limes Britannicus was established in "Isca Dumnoniorum". This was abandoned about 75 AD and the place was elevated into the "civitas" of the Dumnonii. The city of Lincoln was initially the headquarters of the "Legio IX Hispana" and, at the end of the reign of Domitian, was elevated to a "Colonia". It lay on the river Witham, another important communication route. Near the town there was probably a bridge across the river. "Ermine Street" linked London ("Londinium") with the legion camp of York ("Eburacum"). In addition, one of Roman Britain’s main roads, the "Fosse Way", which ran from the west from the