The capital's planned new river crossing faces opposition at every turn. Why has it always been so hard to find new ways across the Thames in East London?
The strangest part of London's planned inner Motorway Box - not just because it's nothing like the other three sides, but also because it actually got built.
The tale of how British traffic signing developed between the Second World War and the mid-1960s, bringing us from a system designed at the turn of the century to the signs we still use today.