From WoWWiki

The Valley of Honor is the location for all things warfare in Orgrimmar. The valley is home to both warrior and hunter trainers, various arms and armor vendors, and the Horde battlemasters. An unused gladiatorial area named the Ring of Valor at the far end of the valley raises questions as to its purpose. The Hall of the Brave houses the warrior guild, as well as all the city's battlemasters. Blacksmithing, mining, and engineering trainers and vendors are found in the valley, as well as Orgrimmar's Weapon Masters.

Subzones of Orgrimmar
Cleft of Shadow • The Drag • Hall of the Brave • Hall of Legends • Grommash Hold • Ring of Valor • Valley of Honor • Valley of Spirits • Valley of Strength • Valley of Wisdom