In short, Grinduro is just what the name suggests: Gravel Road Race + Mountain Bike-Style Enduro = one long loop of pavement and dirt, where finishing times aren’t based on overall loop time, but four timed segments (each roughly five-to-seven minutes).
But Grinduro is not just a bike race. It’s a celebration of cycling with as much emphasis on the fun as the ride, with excellent food, an impressive display of art and incredible handmade bikes, live music, camping and a festival atmosphere.
The course is a serious affair (60 miles of constant up-and-down in rugged terrain) but the Grinduro isn’t meant to be a sufferfest. We’ve linked together some of our favorite roads and trails. Each course features a mix of surfaces (smooth pavement, gravel and hard-packed dirt) long climbs and singletrack descents.
With a Gran Fondo-style mass start, you’ll be pedaling out of town and up the first climb alongside your heroes and the pace will be conversational—because overall time doesn’t matter, only the four timed segments. The Grinduro segments are designed to reward the most well rounded of rouleurs.
You can find more information here