The Grizzly 100 Mountain Bike Ride in San Bernardino, California offers an intense yet rewarding challenge for riders ready to engage with some of Southern California’s most dynamic terrain. Covering approximately 103 miles, with an elevation gain exceeding 11,000 feet, this route demands stamina and skill as it weaves through the San Bernardino National Forest’s dense pines and rugged ridges.

The trail starts near the quaint town of Angelus Oaks, where the forest trees lean in sharply, almost daring you forward. The paths shift beneath your tires — packed dirt, gravel, and rocky sections test your bike-handling as the landscape ascends and drops in a patchwork of exposures and shaded glades. The forest feels alive, branches whispering with the breeze, and streams pushing their way downstream like eager guides.

From singletrack stretches that demand precise control to fire roads inviting sustained speed, the Grizzly 100 paints a full-spectrum riding experience. The sense of isolation intensifies the connection to the environment: chipmunks skitter underfoot, birds call from high branches, and the occasional deer observes silently from a distance. Each climb pays off with open vistas where the San Bernardino Mountains boldly trace the horizon — views expansive, sharp, and spacious.

Planning this ride requires respect for both distance and elevation. Start early, preferably in late spring through early fall, when snow hazards recede and daylight stretches long. Hydration is critical: carry at least three liters of water and have a filtration method handy to refill at trusted spring points. Footwear and bike setup matter—mountain bikes with sturdy suspension and grippy tires will handle the variable trails. Prepare for sudden weather shifts; layered clothing offers flexibility for moments when the forest cools or the sun beats down.

Expect the ride to take between 8 and 12 hours depending on skill and pace. Pace yourself through the harder climbs and take breaks in shaded areas to avoid overheating. Food should be calorie-dense but light, geared toward keeping energy steady rather than spiking.

The Grizzly 100 is an encounter with a force that's fiercely itself: the trail does not yield but it rewards careful and persistent riders. Whether you're a seasoned veteran or an ambitious enthusiast, this ride will push limits while offering the raw thrill of mountain biking in an environment that demands respect and attention.

If you want a solid day of adventure that tests your body and immerses you in a landscape charged with natural energy, this is a trail to consider — where every mile reveals something untamed, something waiting to be understood.