Free camping! Located off the S22, border of Anza Borrego,just 3.5 miles past the town of Ranchita. If you keep going down the hill you'll hit Borrego Springs. Keep an eye out for the Culp Valley Camp sign because otherwise there isn't much indication. Barely any service so make sure you prepare well for an extended stay. It does extremely windy here, especially in early fall with the Santa Ana winds. Hot during day, frigid at night. It's primitively camping so No water, picnics tables, fire rings, and charcoal grills, but vault toilets and ground to put a tent on are available. In Culp Valley there is TONS of boulders to climb; varying from beginner v0's to advanced bouldering. Check out mountain project to check out some routes or just go spot out some of your own! This is place is definetly worth a weekend trip, but Shhh try to keep it a secret. ;) 

Campground coordinates: 33.220541, -116.458858 (33° 13′ 13.94″N 116° 27′ 31.88″W)