If you head towards Lake Martinez just before the marina you will see the right turn to the preserve. The paved road ends to a flat packed dirt 2-lane/sometimes 1-lane road to the preserve. There is little to actually see there but it is an interesting drive.
If you are more adventurous (as I was) continue past the preserve to the various viewing areas. I will warn you the road is rocking and rutty but not impassable in a normal non-4 wheel drive vehicle just be prepared for a slow drive but heck enjoy the scenery.
As always there is no cell service out there so always pack water and food anytime you venture into the desert.
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