Hundreds of commuters braved a winter morning to ride the underground in their underpants.
The exhibitionist travellers were taking part in the ninth annual No Pants Subway Ride which started in New York in 2002, reports The Sun.
The event has since gone global with hundreds of commuters in countries including the UK, Mexico, Japan, Argentina, and Sweden all flashing their boxers, briefs and knickers.
The event organisers Improv Everywhere said its mission was to cause "scenes of chaos and joy in public places".
New Yorker Brady Kirchberg, 26, taking part in his third no-pants ride, said: "It's a place to meet people that's not your traditional bar scene."
Ashley Kemp, 24, said: "I just wanted to do something fun and spontaneous."
The event started in 2002 with just seven people.