Not literally a marathon. But I'm aiming to run 50 miles to help MOO collectively "run from London to Denver". Again, not literally (it's mainly sea), but we're aiming to rack up a few thousand miles. 

I'm doing it for the RSPB to help them, in their own words, "give nature a home". Not just for birds, but for hedgehogs, frogs, eels and all those weird insects. Yes, even flies.