The fort of Kargath, in the Badlands, contains a key Horde Flight Path connecting the north and south of the Eastern Kingdoms. More so than other regions of its level range (35-45), the Badlands is fairly difficult for Horde to reach. The only entrances to the region come either through Alliance territory far from Horde flight paths (Loch Modan) or high level areas far from Horde flight paths (Searing Gorge). There are a few alternatives. All of these assume that you are traveling from Orgrimmar, but it should be fairly obvious how to alter them to account for alternate starting points.