This place is desolate and dangerous WYO desert with very few amenities nearby, and zero assistance should you find your pretty-little-self in a bind.
The people are ornery and the land is mean. I don't recommend coming here at all. If the rednecks, miners, roughnecks vagabonds or land doesn't get ya, some dehydrated whacked-out windblown sunbeaten climber just might. . . . Sweetwater Rocks and adjacent areas require LOW-profiles and LOTS of respect and consideration. Keep all fences/gates as you found them. Do not build fires. Adhere to all posted signs. Do not drive off of existing paths (roads). Do not let your dog run around (chances are great that it'll be shot, bitten, trampled or fed upon). Do not take anything from this land. . . and do not leave anything. Good BLM quads are essential (make sure they're up to date). Granite Mtns (Sweetwater) area closures are adjustable and are done so via ranchers and BLM officiales. Great tracts of this area are privately owned; meaning that they are always closed. For example: Lankin Dome BLM as of last year was closed 04-30 thru 06-31 for public AND private lands; between 03-01 thru 04-31 it was closed on private land. So, sometimes private easements are opened, and sometimes they aren't. . . same with public lands; oh, and mining claims too! Pay particular attention to any signage and postings.
Located just north of Hwy 287. . . west of 220, and east of Lander (see: Jeffrey City). Cranner is a rest-stop/historical area (with pit toilet). Split Rock was an Oregon Trail and Mormon Trail landmark. The Sweetwater River passes through here; enroute from the Wind River's. . . though not so glorious in this area.
If you do venture far from Cranner then also be aware of abundant POISON oak, ivy, snakes, tics bats bugs lizards canids felines bulls cows horses deer moose griz rodents birds ranchers named Bud aliens ghosts and ancient hosts (and all the ornery flying critters you can think of). . . .
The rock 'round here is excellent. . . NO! I mean, scabby, putrid, exfoliating granite. . . not nearly as good as the worst in Fishers.
One more . . . watch out for slung lead. The rednecks, redskins and Red Army in these parts prefer shooting to damn near anything - as do the miners and roughnecks, and some climbers maybe.
EDIT: If you are looking to boulder in mass, this location is prime territory. It is exposed to lots of sunlight all day as well as wind, harsh temp switches. The rock consists of "Gritty" granite stones from small car size boulders to emense two and three story walls.
Getting There
That's up to your preference, and not of much concern (better have 4WD - see Gazetteer & quad - try BLM 2404, then east, north of Bills Peak complex). . . . It's getting out that you should be preparing for; and legend has it, once you're in, there's really no way to truly get out. Look, really, this place ain't worth your life is it?? Head down the road (east) to Fremont Canyon and the water - or try the more sophisticated stuff around Lander. May we never speak of this again. . . .
EDIT: From Laramie take the I80 to Rawlins, turn right on HW 287, follow all the way to Muddy Gap Junction, turn left and drive 25/30 miles to Split Rock/ Lankin Dome area. From casper jump on the HW 220, turn right on to Muddy Gap Junction, follow 25/30 miles to Lankin Dome/Split Rock turn-off.
The Classics
Mountain Project's determination of some of the classic, most popular, highest rated routes for Sweetwater Rocks:
Find the overhanging face, on the right side is the crack that you can't miss.Climb the crack with a bouldery start, at the base is a left facing corner. A two bolt anchor at the top. I took a guess at the name as this rock has this name....[more]Browse More Classics in WY
Poisonous lizards...you are right, I was actualy bitten by a komodo dragon after I refused to share my moose steaks. I nearly lost my right leg, it's still weak and now I walk with a pronounced limp.
yes, this is a vvvverrrrry dangerous area where insane, perverted locals lurk behind innocuous sagebrushes waiting to pounce on anyone with Colorado, Utah, or California license plates and commit unspeakable acts upon them. venture here at risk to your reason.