Campgrounds in the Custer National Forest in Montana

Woodbine Campground which is 7 miles past Nye MT has a whopping 44 campsites.
It has a scenic trail to Woodbine Falls, access to fishing & hiking.
At an elevation of 5,300 feet , it is rated 5 stars by 81% of it's users.
GPS Info. (Latitude, Longitude):
45.35222, -109.89639
45°21'8"N, 109°53'47"W
From Columbus Mt go south on Hwy 78 to the Fish Tail/Nye turn off then follow the
road almost to the end the campground is about 1/4 before it ends.

Rattin Campground just outside of Red Lodge is rated 5 stars by59% of it's users.
It's largest site is 40 ft but it is at a double site.
Trailers are prohibited past Site 3 because there is no turnaround.
GPS Info. (Latitude, Longitude):
45.08306, -109.3
45°4'59"N, 109°18'0"W
On U.S. Highway 212, turn off at Rattin Campground Road (Forest Road 379;
formerly Eastside Road) and proceed 0.5 miles to the campground entrance on the left.

Sheridan Campground just outside of Red Lodge is rated 5 stars by 49% of it's users.
It's largest sites are 30 ft max.
GPS Info. (Latitude, Longitude):
45.10139, -109.30222
45°6'5"N, 109°18'8"W
From U.S. Highway 212, turn off at Eastside Road and go 2 miles to the campground.
The entrance is on the left. 

Basin Campground 
It is rated 5 star by 77% of it's users.
14 of the sites are under 30', 5 are 30', 9 are 32' and 2 are 40'
GPS Info. (Latitude, Longitude):
45.1625, -109.39167
45°9'45"N, 109°23'30"W
From US Hwy 212, travel to the south end of Red Lodge, MT. Turn west on 
West Fork Rock Creek Road (Forest Road 2071), and proceed approximately 
7 miles to the campground entrance on the right. 

Cascade Campground is farther up the same road as Basin, it is in an area where the trees were mostly burned out but it sits right on the creek for easy access. It is only rated 5 star by 46% of it's users. It has 30 sites, 1 is 40', 6 are 30' the rest are smaller.

Parkside Campground is the next campground up hwy 212, it has 26 sites and is rated 5 stars by 70% of it's users. The largest back in site is 50'.
GPS Info. (Latitude, Longitude):
45.06194, -109.40889
45°3'43"N, 109°24'32"W
From U.S. Highway 212, turn off at Rock Creek Road (Forest Road 2421). Go 0.3 miles to the campground entrance on the right.

Limber Pine Campground is just across the creek from Greenough and has only 13 sites, it is rated 5 star by 70% of it's users and the largest back in site is 60'.
GPS Info. (Latitude, Longitude):
45.05833, -109.41222
45°3'30"N, 109°24'44"W
From U.S. Highway 212, turn off at Rock Creek Road (Forest Road 2421). Go just over a mile to the campground entrance, which should be on the left. 

Greenough Campground is the last of the campsites off hwy 212 before the pass, unless you are looking for secluded camping off of Forest roads then it would be MK. Greenough is rated 5 star by 65% of its users and has 18 sites, the largest is 60' back in the smallest is 28'. The trailhead to Greenough Lake starts by campsite #11.

GPS Info. (Latitude, Longitude):
45.05611, -109.41278
45°3'22"N, 109°24'46"W

From U.S. Highway 212, turn off at Rock Creek Road (Forest Road 2421). Go 1 mile to campground entrance, which is on the left.