Sugarloaf Ridge is a well-known mountain bike ride option in the North Bay. This does not imply that it's superior in any realistic sense of the word. The park provides really only one short loop option (it only contains about 10 miles of bike-legal trails, with no trail-based possibilities to extend your ride), the climb of that loop is on a paved road, and the return is on a trail that varies between a fire road and a doubletrack. Especially considering the fact that Sugarloaf Ridge is only a couple of miles away from a mountain biking wet dream like Trione-Annadel State Park, you'd have to be either misinformed or really must have had enough of Annadel and be looking for something—anything—different in order to opt for riding at Sugarloaf Ridge instead.

In all fairness, though, Sugarloaf Ridge does have a few things going for it. The geography of the park is beautiful, with a mix of conifer trees at the higher elevations and a gorgeous mix of oak and bay trees closer to the creek beds, with some bare spots as well as chaparral mixed in here and there to break any monotony. In addition, wide-open views in all directions from high elevations and a seriously challenging climb that experienced riders might like to sink their teeth into are two things Sugarloaf Ridge provides that Annadel doesn't.

Parking within the park is subject to a fee. As of this writing, this fee is $8. There aren't too many other parking options in the immediate vicinity. I did see one or two other pockets of roadside parking along Adobe Canyon Road on the way to the park entrance. However, unless you ride here frequently enough that the fee becomes a budgetary issue for you, I hope that you'll opt for parking in the paid lot as a way of supporting our parks. State parks often aren't exactly rolling in cash, and if they close due to lack of funding, you and I would be among the first to suffer.

This ride route represents the typical Sugarloaf Ridge loop, which probably constitutes something like 80% of all mountain bike rides that are done in this park. This has little to do with the desirability of this route as the best option among many, and more to do with the fact that it's pretty much the only ride option allowed by the park's trail use restrictions, as I mentioned above.

On this ride, you start out by taking Stern Trail to Bald Mountain Trail, on which almost the entire climb is done. Ordinarily, climbing on a dirt trail could be considered to be more fun than climbing on a paved road like Bald Mountain Trail, but in this particular case, it's probably a blessing that the trail is paved, because it's so steep in some places that the lower rolling resistance of pavement is hugely welcome. Bald Mountain Trail is not a very evenly graded climb. On one hand, this might sound advantageous since your climb will be broken up with gentler stretches where you get to rest a little. On the other hand, however, this also means that the steep parts end up steeper than what the slope would have been if the grade were even from beginning to end. There are quarter-mile stretches on Bald Mountain Trail where the grade averages 14%. In shorter bursts, it's fairly common for it to reach or exceed 20%. I'm fairly certain that, at a couple of spots, it even approaches the "ridiculous territory" by getting pretty close to 30%.

Just under half a mile before the end of the climb, pavement ends and Bald Mountain Trail becomes a gravel road again, as well as seemingly doubling its slope. Thankfully, the climb is over very shortly after that, with the first stretches of Gray Pine Trail bringing you right to the peak of Bald Mountain. There are a couple of interpretive panels at the peak that will help you identify the mountain peaks as well as other points of interest that you can see from there in every direction. The views from the peak are expansive. I remember reading that even the Sierra Nevada range is visible if you happen to be here during ideal visibility conditions.

After the peak, other than a couple of brief interruptions, Gray Pine Trail is a descent all the way back to the parking lot. While rarely very narrow, this fire road does look more like a doubletrack in a number of places. The descent is usually very steep, broken up by frequent "humps" that appear to be aimed at erosion control. There aren't many technical features or rock gardens on this trail (other than one or two rocky patches), but the trail surface is frequently loose and gravelly, not to mention the fact that many of the turns are off-camber. Right before the junction with Meadow Trail, you also get to try out one or (seasonally) two minor creek crossings.

In the final segment of this route, you'll find yourself riding past the signposts for "Planet Walk"; a set of markers representing the planets in the solar system that are spaced in proportion to the actual distances between the orbits of the planets. This is one of the featured attractions of Robert Ferguson Observatory, which you'll also be passing by near the end of this ride.

I don't know of too many ways of varying or extending this ride. Within the park's boundaries, your only additional bike-legal options are an extra out-and-back spur along High Ridge Trail starting from the peak of Bald Mountain, and taking Hillside Trail instead of Meadow Trail over the last mile of the ride. Other than that, your only bet might be to add some road riding into the park as an approach (and return) segment. That idea wouldn't be half bad either, because the last three miles or so of Adobe Canyon Road leading up to the park is as pretty as any such verdant canyon road can be. Adobe Canyon Road would actually make for a beautiful road ride by itself, if only it weren't so short.