The No Pants Subway Ride began 13 years ago as a stunt by a New York City improv group. Since then it has expanded to some 60 cities around the world in what is described as a "celebration of silliness."

The No Pants subway website explains the event further: "Random passengers board a subway car at separate stops in the middle of winter without pants. The participants do not behave as if they know each other, and they all wear winter coats, hats, scarves, and gloves. The only unusual thing is their lack of pants."

The event has certainly caught on in Toronto, where photographer Katherine Holland captured some heads turned by bare legs during Monday's otherwise ho-hum commute.

Click through the photo gallery to view Katherine's photos, or watch the YouTube video below to see the shenanigans from last year's event in New York, which regularly draws thousands of No Pants participants.