(05 Mar 2022, 12:55 pm)OrangeArrow49 wrote So what's the full numbering?.Close enough. The 2xx tended to be east and south east Durham.
2xx = Durham (204)
3xx = Wallsend / North Tyneside (306, 308, 309, 310, 333, 335, 392, the 1 used to be 301)
5xx = Sunderland (558)
6xx = Hexham (683, 684, 685 etc)
7xx = Gateshead? (792, 794)
8xx = Northumberland (808, 815, 885)
5xx was mainly South Tyneside.
North and west Durham tended to be 7xx.
6xx was less specifically Hexham and more the far side of Gateshead and beyond. The 638/639/649 never touched Hexham for example.
Local Gateshed services traditionally had the two digit system that you still see around Old Durham Road and Bensham Bank.
2x was Durham Road. 5x mainly Old Durham Road. 6x Dunston area and 9x Lobley Hill/Whickham.
You also had the 1xx series that was used in Washington and Sunderland.
Obviously there was the odd exception (292,293,294 in Washington for example). But in the main, that's what it tended to be.