The C2C Guide webpage providing a guide to the whole of the Coast to Coast (C2C) route from Whitehaven or Workington to Sunderland (Roker) or Tynemouth :- www.c2c-guide.co.uk
The "Sunderland C2C" webpage created by the Sustrans Ranger team in the Washington area :- www.c7c.org.uk covering the route from about Consett towards Sunderland.
The Hadrians Cycleway from Ravenglas to Tynemouth, created by the Tyneside Sustrans Rangers. We rode this route in 2007 and found to be an excellent ride. The only comment I would make - was that there was limited accomodation in Silloth so book early. Although I guess this will change in time, as the route becomes more popular.
The Reivers cycle route from Whitehaven through Kielder forest and onwards to Tynemouth. We rode this route in 2006 and had a problem getting through Kielder due to the forest track being closed due to a Rally being staged. I would recommend checking before you ride, the alternative route via Newcastleton,we found was a bit of a climb from the bridge on the outskirts of the forest.
Not a cycle route as such, but a website for mapping rides that you have done and wish to share with other cyclists www.mapmyride.com