The Blackrock Depths (BRD) are the deepest parts of Blackrock Mountain, ruled by the Dark Iron dwarves led by Emperor Dagran Thaurissan. Blackrock Depths is one of the few sources of Dark Iron Ore and the Black Forge required for smelting the ore is located within. It is also the location of the Black Anvil, which is required by blacksmiths for crafting any dark iron equipment.

BRD is fondly remembered as the most epic of zones prior to raiding--with almost two dozen bosses and many questlines, it was truly an experience back in vanilla. In the past two expansions, areas were tweaked to make travel quicker between bosses via the addition of mole machines and questlines have been removed such as the Onyxia attunement.