One of the best rides around, this features some gravel road, a cross-country style section, some smaller hills with easy turns, and a climb (some parts you might have to hike up). There are very good views along the ridge and a fast downhill featuring tight switchbacks and technical turns.
The best time to ride this is first thing in the morning to avoid the heat, even so, bring plenty of drinking water. Be on the lookout for hikers as this is a shared trail.
Stay on the trail as there is a lot of poison oak in the woods. Additionally, there is also wildlife all around the lake, keep an eye out. Once you are done, enjoy a cold beer and awesome burger at the main marina store.
Once you enter Lopez Lake stay on Lopez Dr. all the way to the end where there is parking on the left, park there and start your ride on the dirt/gravel road to Camp French. Once you've reached Camp French, take the trail back towards the lake (Duna Vista Loop) following the signs.
About a mile into the hard packed dirt you'll encounter some rocks and roots, you'll come to a Y in the trail. You are now at the bottom of the Duna Vista Loop, which is normally taken clockwise, so stay to the left and keep going. The trail is singletrack from here on out and it follows the lake edge, depending on water level. This is a nice easy ride with some small hills and a few rocky turns. After these smaller bumps there's a big climb to the top. It's up to you whether you ride or hike to the top as it gets very steep. Watch your step as the trail is narrow with some loose rocks and small ruts. Given your direction of travel, the mountain will be on your right and cliff on your left. There are trees that provide shade along the way. so use them for your rest spots.
Once you reach the top you can choose to take the Duna Vista Spur
trail to your left. This is an excellent MTB trail, with narrow singletrack, good flow, and it's not too steep. There's a viewpoint at the end of the dam and beyond to the dunes. Enjoy the view for a while, then return to Duna Vista Loop.
Once back on Duna Vista Loop, within the first 50-yards, there is a small trail to the left leads up a short but steep hill, leave your bike on the main trail and hike it. The views at the top are to die for!
Once you catch your breath, head back on the trail and enjoy the views as you ride the ridge. Enjoy the fast-paced downhill but be careful, there are switchbacks with tight tricky turns. Every turn has its own challenges, from rocks, roots, trees, or all of the above. It only takes a few minutes to get back down to where the "Y" in the trail is, after the fast descent, ride back on the trail you rode in on back to where you parked. there are many deer/cattle trails that cut across the dry lake bed if you are looking for a short cut.
Don't forget to head to the main marina and get a cold beer and an awesome burger!