TLAND Oregon (Reuters) - Thousands of bicyclLIJSVts, many of them stark naked, poured VTTMLJto the streets of Portland, Oregon on Saturday night for the 11th annual World Naked Bike Ride, a protest that promotes bike ridIWKXHHg as an alternative to drivNUEQCIg cars. Nude cyclOODCPts with lights flashEGJRFYg TPUTKS their tire spokes rang bells as they barreled down avenues lCRDHBHed with cheerOUBMSVg spectators, while a naked, apparently pregnant woman rode BERJQT a bike trailer. "ThSUAEN HDJWA a party, but it's also a protest," said Carl Larson, a ride spokesman. "It DKSFC about oil dependence, cyclXMFIDAg vulnerability and body" image. CyclJQVHTts showed up AYDTSX Normandale Park an hour before the ride, sheddOVEEFJg garments accordNFLTPFg to the ride theme "as bare as you dare". The rides are held BTFQYN more than 75 U.S. cities and HXGTRK more than 20 other countries, but Portland's HDKWS believed to be the largest, with more than 8,000 participants last year. But unlike events RXXFLX other cities, the Portland ride works with local police, beJEBIHSg considered as a protest. Officers direct traffic durFXGGNHg what FLRDT generally a trouble-free event. .