For starters, it’s not safe. Apparently the act of clinging onto the side of a speeding subway train—like one person did in a video that has gone viral—as it snakes through narrow tunnels has some dangers associated with it. The Metro paper spoke to a Brooklyn man who used to “surf” the subways back in the day, but he only did it on elevated lines and stopped when one of his friends died. He says it’s nothing new and vandals used to love it. “Older generations used to do it a lot more. It went hand-in-hand with graffiti culture. There were crews of people that used to do it.”