Thousands bared what they dared on Saturday to participate in the annual Philly Naked Bike Ride.

The ride began near 31st and Powelton at Drexel Park and went on for two-and-a-half hours, passing down Market Street and through Center City before it dissipated into after-parties around the city.

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This was the sixth naked bike ride in Philly since the tradition began in 2009 -- inspired by the World Naked Bike Ride in 2004.

Why bike nude? Among the goals of the Philly Naked Bike Ride are "to encourage everyone to embrace nudity as a normal, enjoyable way of life" and to "desexualize nudity," organizers say.

And also, because it's fun.

NSFW: Click to see the entire NSFW gallery from the Philly Naked Bike Ride on Aug. 29, 2015. Caution: includes some nudity. Not intended for anyone under 18.

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