Quite an uneventful critical mass, last Friday 27th of March 2013, from where I was riding – apart from a fire emergency situation that gave police a justified reason to divert the ride.
From the South Bank over on to Waterloo Bridge, then through the underpass, towards Holborn and then all along Oxford Street, down Park Lane, Hyde Park Corner, Harrods, the Museums, Draycott Place, Sloane Square, then straight to Her Mayesty’s dwellings (opposite anyway).
There was music and dancing and videoing while some went round and round Queen Victoria Memorial. From there to and over Westminster Bridge, almost all the way to Elephant & Castle and back to Westmister Bridge to approach Waterloo Bridge from the South, and again over the bridge to turn East over The Strand, towards Bank and the London Wall and beyond.
Some links:
http://www.mapmyride.com/workout/250507606
https://www.youtube.com/watch?v=XIJu0UsDCDg
https://www.youtube.com/watch?v=IDErWFzOCic