Unlike many other pre-Grouping companies the NER had a relatively compact territory, in which it had a near monopoly. That district extended through Yorkshire, County Durham and Northumberland, with outposts in Westmorland and Cumberland. The only company penetrating its territory was the Hull & Barnsley, which it absorbed shortly before the main grouping. The NER's main line formed the middle link on the Anglo-Scottish "East Coast Main Line" between London and Edinburgh, joining the Great Northern Railway near Doncaster and the North British Railway at Berwick-upon-Tweed.