Marathon routes for walking

Hi

I'm sadly unable to run due to illness, but am looking to train up to walk a marathon this summer as part of a charity campaign for CFS/ME.  I'm looking for any marathon (or half marathon) routes in London and the South East that I could use as a basis for the walk, but don't know if there's somewhere out there that has defined routes for people to use?

Any resources or pointers would be really appreciated!

Best

Steve

Have a look on mapmyrun.com.  People draw or import maps of race routes, which you can search for, or look for routes in your area.

What about the thames path? im sure i read somewhere that, thats a nice run/walk. It might have even been on this website.

Good luck. 

Thanks! Mapmyrun is awesome, giving me a heap of choices.

Just what I needed.

Try the Long Distance Walking Association - they have planned walking events of marathon distance and beyond...

http://www.ldwa.org.uk/challenge_events/events.php