Napa Valley Spring Half Marathon & 5K

Napa Valley Spring Half Marathon & 5K takes place in Napa, California, on April 25, 2027. Two distances share the morning: a half marathon (13.1 miles) and a 5K (3.1 miles), both on the road in the Napa Valley.

The pairing makes this an easy event to plan around, whichever shape your spring is in. If you have been building mileage since the winter, the half is a natural target: 12 weeks with a long run climbing to 11 miles and one weekly tempo session of 20 to 30 minutes at goal pace will get you there in good order. If your training has been patchy, the 5K keeps the day worthwhile without asking for a full block. Late April in northern California can warm up quickly once the sun is out, so start conservatively and take fluid early rather than waiting until you feel thirsty.