M25 route

Fair enough - I like the irony of debate the relative lengths of recce rides when the ultimate intention is to ride 200+km in a day!

Of course, once we know the ***ing way! ;)

East/North-East is my part of the world so that bit suits me. On the subject of marketing it I'm guessing this forum is a good a way as any in the first instance - many of the rides I've seen organised here seem well attended. Of course it would be fantastic to run something like this as a sportive/audax but in reality an 'informally' arranged leisure ride, albeit with groups of differing ability (say 20,17,15mph paces), would be the best option. I'd be happy to produce (or contribution to the production of) route cards/maps/info etc..

I guess the real issue about organisation (beyond selecting the actual route) is how many people are genuinely going to be up for it.

I think with a ride of this length you either have to be patient or have it taken over by sportive roadies.

What about starting from Thurrock (where if I'm not completely wrong the Dartford Bridge people are based, too) and doing as far as we manage on a Saturday soon? I could make the 16th May, I think--Saturday week.