While London opens its houses this weekend, Boris closes its roads on Sunday for London's annual mass bike ride. We won't use the official title, since it seems to change each year. The event has been popular in the past, and makes for a great way to see some of London's landmarks from a bike saddle (or nip between Open House venues) without worrying about being crushed between buses.
The route will be traffic free, allowing cyclists to pedal peacefully about town, and the event offers other entertainment such as bike stunt shows, a family zone with lessons for the little'uns, a "bike make-over" spot, and, er, Kelly Brook.
The Mayor of London's Skyride takes place on Sunday, with the route closed to traffic from 10am - 4pm, and other entertainment in St James' Park. You can register in advance, or just riding up on the day should work too. If Sunday gets you back on your bike, you can still take advantage of the led commuter rides on Fridays, and the led local rides to discover the best routes near you.