Londoners ditched their pants on Sunday (8 January) and hopped on the underground for the 12th annual No Trousers Tube Ride.
Organised this year by The Stiff Upper Lip Society, images from the event showed people taking the Underground wearing Tube-themed pants, using ticket machines and escalators without trousers, and riding the Elizabeth Line while only partially suited and booted.
The event was part of The No Pants Subway Ride, an annual global event started by Improv Everywhere in New York in 2002.
Other cities around the world are said to have taken part in the fun.
Inevitably, people were left in hysterics and turned to Twitter to comment on the bizarre movement.
One person tweeted: "The annual 'No Trousers tube ride' is one of the most incredible/insane/ridiculous traditions and I'm just sad I wasn't in London for it today. Love how everyone just carries on with their normal commuting as if it's completely normal."
"My absolute favourite thing about these pictures is all the other people on the Tube being typical Londoners and just refusing to acknowledge they're there," another added.
Meanwhile, one unsuspecting passenger quipped: "Today I learned that no trousers on the tube day was a thing."
According to the London organisers, the last time the event was held over 200 Londoners took part.
The Facebook event instructed participants to gather on the street in “normal winter clothes” before people were sorted into groups to walk to nearby stations where they would then remove their trousers.
“For the remainder of the journey, sit in the Tube as you normally would. Read a magazine or whatever you would normally do,” the event description said.
“You can wear fun underwear if you like, but nothing that screams out, ‘I wore this because I’m doing a silly stunt’. Wear two pairs of underwear if it makes you feel more comfortable. Don’t wear a thong or anything else that might offend people. Our aim is to make people laugh, not p*** them off."
They added: “Why are you doing this? You could be solving world hunger/saving damsels in distress/promoting world peace with your time. Surely ‘it’s fun’ is a good enough reason?”
An afterparty in Soho was also organised by The Stiff Upper Lip Society.
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