Rio del Lago

Rio del Lago takes place in Granite Bay, California, on November 7, 2026. The event offers two trail formats, a 100-mile and a 50K (31 miles), both starting at 5:00 AM. The pre-dawn start gives 100-mile entrants the maximum amount of daylight, and 50K runners the chance to finish before the afternoon.

The 100-mile is the main event and a popular late-season goal for Northern California ultrarunners, ideally after a 50-mile or 100K finish earlier in the year. The 50K is a good first ultra or a sharp tune-up for those on a longer program, and it lets you experience the atmosphere of a 100-mile start without committing to the full distance. For either format, train on rolling foothill terrain with a mix of singletrack and fire road, include a few early-morning runs to adapt to the 5:00 AM start, and for the 100, rehearse night running with the gear you intend to race in.