A Cross-Country Crusade Against Pointless Bike Deaths

Today is the 20th anniversary of Critical Mass, a movement of bicycle riders who gather to ride through cities on the last Friday of every month, which began in back in 1992. Critical Mass is considered something of a protest against car-dominated city street systems, but San Francisco now boasts the third-highest share of bike commuters among major U.S. cities. In many ways, the event will be a celebration of how far riding has come.

Of course it still has a ways to go. There to remind cyclists just how far will be Em Baker, who is planning to ride some 3,000 miles from San Francisco to Orlando, beginning the day after the Critical Mass anniversary, exploring the safety hazards of biking in the United States. Baker intends to weave the experience into a documentary called "Spoke."