Traitors Gate
Traitors Gate is the exit where Dimwell Street meets the city walls. According to the map contained in The Compleat Ankh-Morpork, this is the exit point for those wishing to get to Jowser Cove and that point in the Central Continent, opposite El-Kinte in Klatch, which is as far Turnwise as it is possible to get without getting your feet wet. Holy Wood is apparently in this region somewhere. The expanded map in The Compleat Discworld Atlas confirms this.