An eerie, dense fog has sparked travel chaos across the UK Tuesday.
Dozens of flights have been cancelled at Heathrow after thick fog engulfed the west London airport.
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A plane lands in heavy fog at Heathrow Airport
Fog also caused flight disruption at Cardiff airport.
By 10am a total of 85 flights at Heathrow had had to be axed and there were delays to a number of other departures and arrivals.
Heathrow staff advised passengers to check with their airline on their flight's status.
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With the fog taking time to clear in west London, further flight disruption was expected during the last part of the morning.
At Cardiff, a number of flights were delayed and some were diverted to other airports.
The Met Office which gave a yellow "be aware" warning said patchy dense fog reduced visibility to 50 metres in parts of mid, south and west Wales.