Critical Mass bikers travel down 3rd street in mass with the supervision of SFPD San Francisco California.
Image credit: Eric Broder Van Dyke on

When I moved to Miami, FL, in 2007 to start my first job as a journalist for the Miami New Times, I considered myself something of a bicycle guy. 

But Miami was not a bicycle-friendly city. It was a city designed for cars, and taking to the roads by bicycle required some skill and no small amount of either courage or foolhardiness, and I at least possessed the latter. 

We were riding the tailwinds of a dying movement.

As I kept up the biking, however, I found friends—other people who shared a love of urban bicycling and the scrappy, DIY vibe that came with it. We became a community, riding in packs. Our comradery attracted more like-minded folks, and at some point, we found ourselves at the core of a new, semi-organized event in Miami: a fledgling Critical Mass ride. 

Every month or so, our group would gather and then head out en masse, winding as a leaderless blob of bicycles through the streets of Miami. Our group grew in numbers, for a while anyway, and it felt like the beginning of something at the time. 

In retrospect, we were riding the tailwinds of a dying movement. 

If you’ve never heard of Critical Mass, it’s understandable: the bicyclist/activist movement, which peaked in the 1990s, appears to be more or less dead in the United States. 

But for a long time, Critical Mass rides were a thing: in cities across the country, hundreds of bicyclists would gather regularly and take over the streets in a mass ride.

The rides were, by design, unpermitted by any authority. Critical Mass rides would block traffic, often with participants literally placing themselves as human-bike barricades at intersections—a practice known as “corking”—to allow other riders to pedal on with ease and, crucially, without fear for their safety. This tended to irritate some drivers, which was part of it. Sometimes things got confrontational—sometimes extremely confrontational. 

Critical Mass had a party vibe, to be sure, but it was also meant to convey a message: that streets belong to everyone, that everyone using them should feel safe doing so, and that the present reality didn’t live up to these standards. The idea behind the rides was that a “critical mass” of riders could change that equation by taking over the streets and transforming that dangerous public space into one of safety and celebration. It was both a party on wheels and a mass act of rebellion. 

It was, like it or hate it, a genuine social movement—a growing one, for a while, that spread out across the United States. And then, Critical Mass essentially vanished. Why? 

What Happened? 

The demise of the Critical Mass movement is clear. For a while, at least, dozens of US cities—including Seattle, Chicago, Philadelphia, and Portland, OR, to name a few—had prominent Critical Mass rides, and now they don’t. Some, like Portland’s, ended in headline-grabbing crackdowns by police and local officials. Others appear to have just fizzled out. 

I should note that the movement isn’t entirely dead—a cursory investigation found remnants here and there: ongoing Critical Mass rides in San Francisco, a newly-constituted ride in Pittsburgh, for example. And there’s evidence that Critical Mass, or something similar, is just now taking off in places outside the United States. But for the most part, in the places where the movement originally grew, thrived, and then disappeared, it hasn’t returned, at least in easily recognizable form. 

If Critical Mass won some battles, it demonstrably lost the war.

While the decline of Critical Mass is obvious, the reasons for it are less so. In fact, I don’t have the answers—but maybe some of you readers do. 

In the meantime, I offer some theories to kick things off. 

Theory 1: Critical Mass (kind of) won

Critical Mass demanded safer streets for bicyclists at a time when bike lanes and other accommodating infrastructure was relatively sparse or nonexistent in many cities. Since then, thanks in part to advocacy that included Critical Mass itself, many big cities have implemented more accommodations for bicyclists. As a consequence, Critical Mass gradually lost some of its underlying energy as a push for change. 

The problem with this theory is that if Critical Mass won some battles, it demonstrably lost the war: bicyclist deaths are up, not down since the 1990s. Pedestrian deaths are also on the rise in recent years. If the dream of Critical Mass was safer streets, the dream hasn’t been realized. 

Theory 2: The movement became professionalized 

Most big US cities are home (these days, anyway) to what one might call a professional class of bicyclist and pedestrian advocates—generally in the form of local nonprofit organizations that employ full-time, salaried advocates. Some of these organizations are newer, while some date back to the Critical Mass days and earlier—but either way, as cities seemingly granted these organizations more access to the powers that be, perhaps they in turn harnessed the anarchic energy of Critical Mass and channeled it into a more buttoned-down, organized, and professionalized movement. As the reach of these professional, semi-institutionalized organizations grew, the leaderless, anti-establishment Critical Mass movement withered on the vine.

Theory 3: Critical Mass became a party 

Maybe the movement’s social aspects simply won out over the activism. Maybe the activists left.

Critical Mass rides were always partly a festival on wheels, embodying a collective sense and celebration of freedom. The rides were a vibrant social scene that welcomed newcomers, oddballs, misfits, and—importantly—people who were otherwise marginalized for whatever reason. A good friend of mine described his first time participating in a Critical Mass as a “transcendent” experience. Arguably, most participants came for the experience and comradery first and the activism second, if at all. 

Many cities still host some form of mass bike ride, but these are not—by appearance or self-identification—Critical Mass. Maybe the movement’s social aspects simply won out over the activism. Maybe the activists left. 

Theory 4: We forgot how to gather 

As a last half-baked hypothesis, I offer that Critical Mass was a movement born of a kind of physical getting-together that has withered in the Internet era, in which complaining has never been easier. Is it possible that the energy behind Critical Mass was sucked into social media platforms and regurgitated as keyboard activism? 

Perhaps the demise of Critical Mass included all of these elements—or perhaps none of them hit the mark. If you have a theory, please let us know here at NPQ. We just might all learn something new. 

Isaiah Thompson can be reached at [email protected] and is on X @Isaiah_Thompson.