The Northwest Thuringian Forest comprises an area of about 70 km² reaching heights up to , hardly exceeding those of the adjacent Buntsandstein forelands to the southwest, but exhibiting a much more pronounced relief. It stretches until Moosbach stream, a tributary or Erbstrom river, in the north east, and to Bundesstraße 19 in the east and south, which follows the upper reaches of Elte river between the villages of Wilhelmsthal and Etterwinden. The predominant rock species is Eisenacher Rotliegend, namely conglomerates and sandstones. The area is known for the so-called Drachenschlucht, a narrow gorge near Eisenach, and the Wartburg castle. The northern part of the area is drained by several streams into the Hörsel, the southern part into the Elte. Hence, the ridge of the Northwestern Thuringian Forest only forms the watershed between Hörsel and the middle course of the Werra.