From WoWWiki

The Hall of Explorers is home to the famed Ironforge Explorers' Guild (aka Explorer's League). Every archaeological expedition the Alliance sends out is coordinated from here. It also houses the Ironforge museum and the Library.

To get to the Hall of Explorers, you can head northeast from the Great Forge, north from Tinker Town, or east from the Forlorn Cavern.

Subzones of Ironforge
The Commons • The Gates of Ironforge • The Great Forge • The Forlorn Cavern • Hall of Arms • Hall of Explorers • Hall of Mysteries • Hall of Thanes • The High Seat • The Library • The Military Ward • The Mystic Ward • Tinker Town • Vault of Ironforge