With a bit of specialist kit and some twitter friends it is possible to 'do' London as a family by bike.
We took our 2 kids - one primary and one secondary aged -- and our trusty 8 year old Circe Helios tandem down by train. In London, we borrowed another - rather newer - Helios from a local cycling family.
With two panniers that transform into backpacks, we tackled 60-odd miles of London over 5 days. We saw Tower Bridge and toured the Tower. We rode the east-west cycle super highway (CS3) by day and by night. We went to a play in Southwark (Q1) and tackled the Farringdon infrastructure (CS6) in both directions. We pootled around Hyde Park and Green Park, saw Buckingham Palace, and the Horse Guards at Whitehall and visited museums.
While the segregated infra was definitely the best, the permeable connections from Bloomsbury to Angel (Q2) and around de Beauvoir in Hackney (CS1) were pretty good, if not deserving of being called a 'super highway'. The family was also convinced that CS1 took us round in circles until they looked at the Garmin track. The one section that got an overwhelming thumbs down was Exhibition Road, which had a lot of through traffic and where a kid jumping out of a 4x4 nearly doored us.
On the streets, drivers were surprisingly forgiving, although the busses seemed to see us as competition. It being the holidays, there weren't many commuters, but instead a lot of folk cycling to the shops, or, in the city centre, tourists and locals on rental bikes.
All in all, a good trip. We're looking forward to getting home, but we'll miss the infra and the 'normality' of cycling in London. Hopefully Edinburgh will learn from London's mistakes and build only the best.