Subway commuters in London were seen travelling without trousers to mark the annual 'No Trousers Day in Tube'.
Visuals from January 8 show both men and women commuters boarding trains, walking through subways in their underpants.
The idea is to enter the subway car pantless and act like it is any other day.
Not just UK, but the day is celebrated in several other countries as well. The global event was first started in New York as a prank by comedian Charlie Todd. Interestingly, the prank turned out to be such a huge hit that it is practised to this day with as many as 25 countries marking it.
Now the day is practiced every year in the first week of January.
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