Located near the north-western corner of the Grand Exchange, and provides access to Keldagrim. The message when opening the Grand Exchange trapdoor says: This trapdoor leads to a small dwarven mine cart station. The mine cart will take you to Keldagrim.
Uses the same trapdoor behind the Hair of the Dog tavern in Canifis. The shortcut is obtained by training Zachory Bragg in Temple Trekking to level 99. In order to use this shortcut, the option must be toggled on in the character interface by clicking on Zachory Bragg's level 99 description. The shortcut places the player's character next to the swamp boat in south-eastern Mort'ton.