The TV stars stunned commuters by boarding a Piccadilly Line tube train when they realised that travelling by car was not the best option.
Holly and Dermot - who is currently guest presenting This Morning - posed for a couple of pictures during their journey, which were then posted online.
In the first one, the pair can be seen waiting for a lift to take them down to the platform. Holly, however, doesn't seem entirely convinced about getting on public transport.
Uploading it to Twitter, she explained: "Bad traffic...the tube it is! X."
The pair then posed for another snap, while Dermot clutched a copy of yesterday's London Evening Standard newspaper. Holly, meanwhile, held onto the train's blue pole as they sped to their destination.
Commenting on this photo, Holly added: "Ha! @radioleary single zone 1! Thank you TFL! X"
Catching the tube is a rare experience for the telly stars, especially Holly who usually tends to travel across London on the back on a motorbike.
They are by no means the first celebrities to use this method of transport though.
US superstar Jay-Z was pictured on the tube with Chris Martin last October and Rihanna was spotted riding the Jubilee Line in 2012.
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