Thousands in Portland take to bikes for naked ride.

It was a typical early summer evening in Portland. Thousands of naked bicyclists gathered near the city's waterfront for a clothing-free night ride.The Portland version of the World Naked Bike Ride was about to begin.World Naked Bike Ride is a globally observed event among hard-core bikers designed, at least ostensibly, to promote the use of the bicycle for transportation. But Portland cyclists have been especially adamant about making it another of the Pacific Northwest city's quirky traditions.Since the World Naked Bike Ride started in 2004, only four other cities -- San Francisco, Seattle, and Boulder and Black Rock City in Colorado -- have celebrated it every year.The Portland nudist/cyclists have turned the event into a festival, with a pre-ride event and post-ride parties featuring both clothed and naked partying which lasts well into the night.

Portland Police don't arrest the naked riders. They cite the city's extremely tolerant public indecency code as permitting such activities as mass nude cycling.