A small country on the far side of Llamedos with a coast on the Turnwise Ocean. So far not featured in any stories and almost completely virgin ground (except perhaps for the people who live there). The Compleat Discworld Atlas notes that this is the location of the Wyrmberg and massive attempts are made to coexist with noble dragons who are not nearly imaginary enough. Mr Frisk, the resident civil engineer for the Grand Trunk Company's Turnwise Ocean division, notes gloomily that not even the strongest clacks tower can withstand being used as a dragon perch and this is causing some real problems for clacks communications.
The capital city, or nearest thing to, is the coastal port of Smork. Hergen also boasts the Caderack Senior Centre, a respite home for elderly Barbarian heroes, a place where a Hero in his diminishing years can go for Saga Breaks. Hergen even founded one daughter colony, Hergenland.