Greenbrier is a multi-use park providing many kinds of recreation. The Appalachian Trail passes through the park. The 42-acre man-made lake and beach draw many visitors who enjoy swimming, canoeing, hiking, picnicking, fishing and hunting. As with most of Maryland's State Parks, a park map is available at the park office. Located in the Appalachian Mountains, this state park offers many recreational opportunities. The man-made freshwater lake offers swimming, sunbathing, boating and fishing opportunities. There are also hiking trails which meander through a variety of wildlife habitats and afford a view of the area's geological history. Picnic tables and grills and playgrounds are available in the day-use area.
There are a number of trails in Greenbrier State Park to include the Big Red Trail - the longest trail in the park at 4.5 miles. The trail starts down along the lake and makes a nice long loop on the west side of the park. I would rate the trail as moderate with a couple of hills to transverse but nothing too difficult. If you want, you can park on Route 40 where the AT has a parking spot and hike south along the trail until you get to the Bartman's Hill Trail (on the right) which will take you down into the park for a total of 7.5 miles. See attached link for a good map of the trails.
This trail was a pretty good hike. We did the red trail at Greenbrier. It was long. enough and a good mixture of flat, rocky, up hill, and down hill. You can chose to shorten the hike at a few points on the trail by jumping on the blue trail.The only reason I wasn't too impressed is because it was kind of boring. There weren't many good views. Overall, we enjoyed the hike though.