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Halloween Critical Mass

12:19 AM PDT on October 17, 2011

Critical Mass is a mass bicycle ride that takes place on the last Friday of each month in cities around the world. Everyone is invited! No one is in charge! Bring your bike!

Aaron Bialick
Aaron was the editor of Streetsblog San Francisco from January 2012 until October 2015. He joined Streetsblog in 2010 after studying rhetoric and political communication at SF State University and spending a semester in Denmark.

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