An estimated 5,000 cyclists rode through the streets of San Francisco for four hours in the early evening on Friday to commemorate 20 years of Critical Mass, a monthly bike ride that aims to raise awareness of bicycle safety, the Golden Gate Express reported.
The rides, which take place during the evening commute, also "challenge the use of city streets and the domination of cars and oil in our transportation system,” according to the organization.
The first group ride in San Francisco in 1992 inspired similar events in other locations, and these days, Critical Mass cyclists ride together – often snarling traffic – in 300 cities worldwide, the Guardian reported.
On Friday, cyclists rode nearly 20 miles through downtown, the Embarcadero, the Mission and Financial districts, the Golden Gate Express reported.
According to the Golden Gate Express, some cyclists stopped in San Francisco’s Broadway Tunnel to write Critical Mass birthday wishes in soot on the tunnel walls.
The anniversary celebrations also included a Sunday ride to a party at Ocean Beach, the San Jose Mercury News reported.
"There are very few things you can do in this world, San Francisco or anywhere else, that involves coming together in public in motion and in doing so you are transforming your experience of a city,” Chris Carlsson, one of Critical Mass founders, told the Guardian. “And you're not required to buy anything, you're not required to sign up to anybody's religion or anybody's political ideology or anything else, you just come and do it."
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