I’m known around here for my obsession with the capital’s lack of a proper high-speed road network.

London is probably the only big European city that lacks a proper ring road and substantial feeder roads that run close into the centre.

Anybody who has driven around Paris’s Boulevard Peripherique knows that it can be catastrophically busy but that it is also a major benefit to the city. It was completed in 1973, the same year that the London Ringways system was condemned to death.

The state of the traffic on the Peripherique and the feeder roads is clearly a source of major interest to the French.

I snapped this rather neat live map in the reception of the Peugeot-Citroen design centre on Monday. (The lack of red alerts is a reflection of the fact that I took it at 4.00pm; within minutes it was lighting up for the evening rush hour).