We loved the London Critical Mass ride. It’s definitely one for every cyclists calendar!

We left from Waterloo and went around the city, smooth and swift along many streets of London. Including rolling [next to] Buckingham Palace, and the Tower of London

If you want a better report, posts yours to londoncriticalmass@riseup.net or to the list http://lists.riseup.net/www/info/cm-london