Countdowns don’t get any more exciting than this. When conditions are just right, ocean swells pile up against an offshore reef, about 2 miles/3.2 kilometers off Northern California coastline near Half Moon Bay. The resulting break, known as Mavericks (or just “Mavs” to its big-wave fans) creates behemoths breakers regularly cresting at 25 feet/7.6 meters, with some topping out at more than 80 feet/24 meters. When that happens, a select group of 24 surfers (plus alternates) get invited to compete. The catch? Start time is only announced 24 hours in advance, so surfers have to be ready to pack up their boards and go as soon as Mavericks gets a green light. So do the fans. Waterfront lookouts are lined with people peering through telescopes, telephoto lenses, and binoculars, trying to catch a glimpse of the out-at-sea action. An easier option is to join the festival atmosphere in town, usually centered around the parking lot of the Oceano Hotel & Spa. Expect plenty of beach-and-surf music and food; when the competition wraps, stick around for the awards presentation, when surfers often linger to chat with fans.