A busy tunnel which carries around 100,000 vehicles a day under the River Thames has been closed a "staggering" 1,200 times in the past nine months because drivers did not heed height restriction warnings - or ran out of fuel, according to a new report.
The Blackwall Tunnel in east London has closed for 157 hours since last April, causing more than 13 days of serious traffic disruption.
Kulveer Ranger, the mayor of London's transport adviser, said: "We all know how frustrating it is sitting in traffic, even more so when the reason for the jam is so easily avoided.
"We are asking all drivers using the Blackwall Tunnel to use their common sense and make sure their vehicle is not too high to get through and is not likely to break down or run out of fuel in the tunnel.
"It sounds simple but these sorts of problems are causing thousands of drivers to sit in pointless traffic jams for hours on end."