Nudes on wheels: Thousands of cyclists take it off for anti-car protest

Naked for a cause: Thousands of clothing-free cyclists take to the streets of Portland, Oregon, as part of the city's 11th annual World Naked Bike Ride, held as a peaceful protest against the overwhelming use of cars on the road.

Thousands of bicyclists, many of them stark naked, poured into the streets of Portland, Oregon, for the 11th annual World Naked Bike Ride, a protest that promotes bike riding as an alternative to driving cars.

Nude cyclists with lights flashing in their tire spokes rang bells as they barrelled down avenues lined with cheering spectators, while a naked, apparently pregnant woman rode in a bike trailer.