Yes, it's exactly what it sounds like.
On Sunday, brave folks from all over the world took a leisurely ride on their local subway system. The rides were normal enough, except for the little detail in which nobody wore pants to mark the 13th annual No Pants Subway Ride.
It was truly a worldwide under(pants)taking: outlets from all over the place like Baltimore, Berlin, Hong Kong, Vancouver, Sydney, and the UK each reported on the state of undress taking place in their respective fair cities.
The No Pants Subway Ride began way back in 2002 with just seven participants (all members of the group Improv Everywhere) riding the subway in New York City. In the meantime, the yearly winter event has spread to over 60 cities across the globe, all of which come together for an "international celebration of silliness."
There's certainly silliness and shock value for the poor unsuspecting and fully-clothed passengers, but there's also a deadpan quality to the whole thing. Participants are instructed to wear normal clothes on their top halves and are not to acknowledge each other. Some even go about their regular subway activities, such as reading the newspaper.
"If questioned, you do not know any of the other pant-less riders. Tell folks that you 'forgot to wear pants'," riders in Sydney were reportedly told. "Insist that it is a coincidence that others also forgot their trousers. Be nice, friendly and remain calm."
Check out some photos from the Berlin event in the slideshow above. Perhaps someday they'll all be daring enough to try it on a weekday?