Greenbrier State Forest, created in 1938, straddles Kates Mountain near White Sulphur Springs. Like all state forests, it is dedicated to a multiple-use, sustained-yield program. The 5,130-acre forest is richly populated with wildlife. There are deer, racoons, wild turkeys, black bear, squirrels, chipmunks, and the unique Allegheny woodrat, sometimes called pack rat by local people. Greenbrier State Forest also includes the rare Kates Mountain clover and box huckleberry. Swordleaf phlox is equally rare and known in only two other counties in West Virginia. All of these rare plants can be seen in Greenbrier State Forest or within a few hundred yards of its boundaries.

There is a forest demonstration area along Harts Run between the cabins and the campground. This 20-acre demonstration forest is divided into separate plots, each displaying timbering practices. Another attraction is Kates Mountain Road, which runs for miles along the top of the ridge. The road begins at U.S. 60 in White Sulphur Springs, not far from the entrance to the Greenbrier resort, and ends at the forest headquarters building. The road was originally constructed as a scenic drive and for forest fire protection by the Civilian Conservation Corps in the 1930s. Recreational facilities at Greenbrier State Forest include a swimming pool, 14 vacation cabins, picnic facilities, hiking and biking trails, and a campground.