The Dark Iron Highway is located inside Blackrock Depths. This long stretch of wide pavement is located directly north of the entrance (behind a gate requiring the Shadowforge Key), and is guarded by patrols of dwarves, dogs, and the occasional fire elemental. At its western end stands the giant Bael'Gar. The eastern end of the road leads to the Black Anvil.
If the adventurers who wish to fight Bael'Gar do not possess the key or any other means of bypassing the locked door, a long run through the Ring of the Law, Shadowforge City and the Hall of Crafting is required.