If you noticed anything a bit odd on public transport on Sunday, you may have come into contact with participants in the No Pants Subway Ride.
People around the world stripped off their trousers and rode on trains as part of the event, which started back in 2002 in New York.
The No Pants Subway Ride was created by the comedy group/prank collective Improv Everywhere. The event began small, with only seven people jumping on the New York subway in their winter gear, without any pants on.
Now, the idea has spread into an “international celebration of silliness,” according to the group’s website. It is marked in 60 cities, including London, where Brits have made the event their own in calling it “No Trousers on the Tube Day”.
The idea for the light-hearted event is simple: participants get onto the subway at different stops and don’t acknowledge that they are wearing their warm winter clothes with no pants on, much to the amusement and confusion of their fellow passengers.