Tennis player Jamie Murray - the brother of British number one Andy Murray - was caught up in the queues at passport control on Thursday night.
He tweeted these pictures, estimating that there must be a couple of thousand people waiting in line.
He added the hashtag #thirdrunwayanyone?
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Pregnant woman who was labour has had her "phone snatched while calling for and ambulance to hospital".
It will be increasingly cloudy this evening, with sporadic outbreaks of rain or drizzle spreading in during the first half of the night.
A derelict north London garage has gone on sale for £360,000 - more than the cost of a flat on the same road.