There are endless camping possibilities in Kofa. Primitive, dispersed real wilderness camping. No water. No toilets, no hookups, generators... and you have to have a 4x4 to get there! Just my kind of spot. I've explored all over this area by jeep, and by foot and never get bored going off on some new abandoned mine trail. There are hidden caves all around and great hikes to get there!
I'll just share my two favorite hidden gems in the area: Signal Peak is a must, and if you do, I recommend camping around Skull Rock. For a scenic offroad trail + neat cabin stay head to Kofa Mine Cabin!
For Signal Peak and the Skull Rock stay, you can park regular cars along Palm Canyon Road where the Kofa Natl Wildlife Refuge Brochures and info are and hop into a 4x4 for the rest of the drive. You'll need it. Don't attempt get to skull rock in any regular, vehicle, or anything without high clearance.
**NOTE: I have left a car in this lot with no issues while camping up in the canyon over night, but of course, do so at your own risk.
From that parking lot you head up to Kofa Queen Canyon and pick your spots for camping. There are plenty of good spots for tent on ledges, or on cots down near skull rock. Here you can grill and have general campfire fun.
The road to Skull Rock is undeveloped, needs high clearance and is a tight squeeze for wider vehicles. It will not accommodate campers or trailers. Tent camping only (aside from maybe your serious bug out vehicle!)
Skull rock camp spot is about a one hour and 45 minute drive from Yuma. From HWY 95 turn (east) onto Palm Canyon Road (not too far past the Border Patrol Checkpoint. Drive east 3.2 miles to Kofa Queen Canyon (KQC) Road on the left (north now). Follow KQC Road northeast about 7.5 miles into the Canyon to where a subsidiary Canyon opens up to your right (south). Passenger cars won't manage this last road. You'll need high clearance and preferably 4wd. The road inside the canyon is alternately rocky and sandy, and braids in and out with the wash. Just follow the 'better-looking' route if unsure at a junction. Enough people come up here you should be able to see lots of tire tracks.
*NOTE: There is no cell service at the campsite.
From here we drive down the trail bit further to get to Signal Peak (roughly 4,800ft), it's Kofa's highest peak. This is a strenuous hike with steep slopes and some scrambling, and should only be done by experienced hikers in good physical conditions with proper hiking boots. The beautiful view from from the top is absolutely worth the hike.
Dogs: Although I know of people who have brought dogs up here, it is a very rocky hike and could be very hot or treacherous for your pup. You may consider bringing a dog only if he is an avid hiker and has very strong paw pads (or hiking boots), and can physically handle the demands of this hike. Also, dogs as per Kofa National Wildlife Refuge Rules - are required to be on a leash at all times.
For the Kofa Mine Section, head on your way out to the Kofa Mine Museum and then just past it take the turn to Big Eye Mine - 15 mile offroad trail where a real, high clearance truck/jeep 4x4 is needed. There are at least 2 hairy sections that I even got a jeep stuck in for a minute. All of this area is full of mines and great open camping spaces.
Kofa was established in 1939 to be managed: “…as a representative area of lower Sonoran Desert habitat with a maximum diversity and abundance of native plants and animals and to protect and preserve the desert bighorn sheep and its habitat…” Since 1955, over 560 desert bighorn sheep have been trapped on Kofa and transplanted to other areas in Arizona, as well as to the states of New Mexico, California, Colorado, Texas and Nevada, to re-establish herds extirpated from habitat loss, development and over-hunting.
Unless you are a skilled Arizona adventurer, I'd advise against hiking or even offloading (in case something goes wrong) during the hot summer months when temperatures can rise to over 115 degrees F.