Did you know that the mountain bike originated in the Bay Area?
Above is a photo series from the Mountain Biking History and Culture Archive that UC Davis alum Sarah McCullough put together as part of her thesis covering the origins of the sport.
Many of these early mountain bikers were part of the larger counter-culture movement going on in the 1970s. They would retrofit bicycles to use on dirt paths and would then race with them in competitions. This caused a lot of debate over trail access with longtime users of the trails.