Important Heirlooms
Collect 8 Dwarven Heirlooms from the halls for Thom Filch.
Collect 8 Dwarven Heirlooms from the halls for Thom Filch.

Most heirlooms sit in the Reliquary of Kings vaults, which open after the last boss dies.
Thom Filch stands right outside the portal, so you can hand it in on the way out.
Alliance: Thom Filch in Ironforge (32.5, 44.8).
Alliance: Thom Filch in Ironforge (32.2, 44.9).
Dwarven Tome, Tomb Robber's Gloves, 2,950 XP.
Important Heirlooms is a level 15 quest; you can pick it up from level 10. It takes you into Hall of Thanes.
All Hall of Thanes quests on one map ·Hall of Thanes dungeon guide
Sources: Quest data from ForeverDB.net · ForeverDB: The Hall of Thanes dungeon · ForeverDB: Ironforge quests · ForeverDB: Dun Morogh quests · ForeverDB: The Treaty of Understanding · ForeverDB: Old Ironforge Incursion · Warcraft Wiki: Old Ironforge quest chain · Warcraft Wiki: Underground Map · Warcraft Wiki: Important Heirlooms · Warcraft Wiki: Ghostly Attendant