From WoWWiki

Felfire Hill is located in Ashenvale, southeast of Splintertree Post, southwest of the Warsong Lumber Camp, and northeast of the Dor'Danil Barrow Den. It is the site of the arrival of several infernals during the Third War, and is inhabited by all manner of foul demons. The Horde has fortified both bridges leading to the hill in order to prevent attacks on any of their nearby settlements.

Subzones of Ashenvale

Astranaar • Bathran's Haunt • Bloodtooth Camp • Bough Shadow • Demon Fall Canyon • Demon Fall Ridge • The Dor'Danil Barrow Den • Falfarren River • Fallen Sky Lake • Felfire Hill • Fire Scar Shrine • Forest Song • Greenpaw Village • The Howling Vale • Iris Lake • Kargathia Keep • Lake Falathim • Maestra's Post • Moonwell • Mor'shan Rampart • Mystral Lake • Night Run • Nightsong Woods • Raynewood Retreat • The Ruins of Ordil'Aran • The Ruins of Stardust • Satyrnaar • The Shady Nook • The Shrine of Aessina • Silverwind Refuge • Silverwing Grove • Silverwing Outpost • Southfury River • Splintertree Post • The Talondeep Path • Thistlefur Hold • Thistlefur Village • Warsong Labor Camp • Warsong Lumber Camp • Xavian • Zoram'gar Outpost • The Zoram Strand