The velodrome arrived during a boom in American cycling infrastructure, when Cold War-era Olympic ambitions drove investment in track cycling facilities. At 335 meters with a maximum banking of 23 degrees, the Hellyer oval is longer and gentler than international competition tracks, which typically measure 250 meters with steeper banks. That geometry makes it forgiving for newcomers while still rewarding experienced riders who can hold a tight line through the turns. The track was built inside Hellyer County Park, a ribbon of green space along Coyote Creek in south San Jose, where the Coast Range foothills begin to flatten into the Santa Clara Valley floor. Riders finishing a lap on the back straight can see the creek trail below, joggers and dog walkers passing oblivious to the speeds above.

The velodrome's proudest chapter came in 1972, when it hosted the United States Olympic Bicycling Trials. Riders from across the country descended on San Jose to compete for berths on the team headed to the Munich Games. For a modest county park facility, it was a remarkable selection. The trials put Hellyer on the national cycling map and cemented its reputation as a serious track despite its public-park setting. That same year, Mark Spitz was training for his seven-gold-medal swim performance at Munich, and the cycling trials shared the same restless energy of American athletes preparing for what would become one of the most turbulent Olympic Games in history.

A 2004 San Francisco Chronicle article captured the velodrome's enduring character with the headline: "They aren't big wheels." The piece described a scene of weekend warriors and weeknight regulars chasing each other around the oval, nobody famous, nobody paid, everyone hooked on the particular thrill of riding fixed-gear bikes at speed on a banked surface. That grassroots atmosphere has defined Hellyer for decades. The Northern California Velodrome Association, a nonprofit, operates the facility and organizes race nights, training clinics, and introductory sessions for riders who have never clipped into a track bike. There are no grandstands packed with spectators. The audience is mostly other riders waiting for their race, leaning against the rail, studying the lines they plan to take.

Velodromes across America have a history of vanishing. Tracks get paved over for parking lots, fall into disrepair, or lose their constituencies to road cycling and mountain biking. Hellyer has endured partly because of its location within the Coyote Creek Parkway, a chain of county parks that protects the land from development, and partly because the NCVA has kept the facility maintained and programmed. The creek trail that runs beside the velodrome connects it to a network of paths stretching from the neighborhoods of south San Jose toward Morgan Hill, giving the park a steady stream of visitors who discover the track by accident. Some stop to watch. A few come back with a bike. The velodrome does not advertise. It does not need to. Sixty years of banked turns along a creek have been advertisement enough.