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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If you're dreading going to work Monday morning, how about this for a career change.
Police have released more images of people wanted in connection with what they describe as 'disorder' at a McDonalds in central London.
Four teenage girls, one of them aged 15, have been arrested following what police are describing as "disorder" at a McDonalds branch.