"The Woodstock of triathlons" is not only a classic three-race event (Olympic distance, long course, and mountain bike); it's also a massive campout, replete with roaring bonfires and post-race partying for 7,500 athletes and 30,000 spectators in a central-California county park. Competition for good camping spots is fierce, so plan to arrive at the race site by Thursday afternoon if you care about sleeping comfortably. Bring a wetsuit—Lake San Antonio averages 66 degrees—and put your bike in its granny gear for the transition, since the ride starts with an immediate, ramp-like hill (the first of many). The run course is mostly off-road, so bring light trail runners. And pack your allergy meds; the pollen levels are off the charts around the lake in early May. $260; tricalifornia.com