1st-time London visitors seek fun, culture and bikes.

My bad. Most people on here don't seem to venture more than 20k from their door.
With only 2 weeks though I'm not sure they'd be making it too far from London unless they're going to use the trains rather than cycle?

I'll be making my first visit to Wales in a couple of weeks..
http://www.cyclosportives.co.uk/devilHome.htm

be ready some serious climbs mate. devils staircase is a killer (literally) and watch out for the sheep on the road it makes for an interesting collision.