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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A bright and sunny day tomorrow, but feeling distinctly cool and chilly tonight.
An ITV News London investigation has discovered the inquest will now be held at Westminster Coroner's Court.
The family court finalised the adoption as the criminal proceedings were still under way. The couple have vowed to fight for their child.