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The Thüringer Wald (Thuringian Forest) reveals an Upper Stephanian-Rotliegend succession that can be subdivided into eleven formations. These formations also occur in boreholes beyond the borders of the Thüringer Wald mountain range, to the Northeast by about 12 km and to the Southwest by at least 20 km. The Georgenthal and Möhrenbach Formations are in part coeval with each other. They unconformably overlie the folded Variscan basement, which consists of Proterozoic to Lower Palaeozoic formations of the Saxothuringian zone in the SE, a deeply-weathered granitic massif in the middle part (Thüringer Hauptgranit, Visé), and metamorphic rocks of the Ruhla Crystalline Complex in the NW. The Georgenthal and Möhrenbach formations mainly consist of trachyticlatitic volcanics, pyroclastics and intrusives. In addition, the Möhrenbach Formation contains acid volcanics that become increasingly acid upwards. According to lithostratigraphic correlation, the Möhrenbach Formation started earlier and finished later than the Georgenthal formation. The fossil content of sedimentary horizons in the basal or lower part of both formations indicates a late Stephanian age. The base of the overlying Ilmenau Formation contains a typical lowermost Rotliegend flora. The Ilmenau Formation displays a bimodal character of rhyolites and basic rocks that alternated in space and time in local sedimentary basins. The Manebach Formation consists of grey conglomerates, sandstones and mudstones, with some local coal seams. The polymict clastic components indicate that the fluvial drainage extended into regions from beyond the basin margin. In the Goldlauter Formation, coarse-clastic red sediments of marginal alluvial fans and valley fills interfinger with grey lacustrine sandstones, siltstones and mudstones. Volcanic events are restricted to several tuff layers, which are used as tephrostratigraphic marker horizons. The sedimentary patterns indicate considerable rejuvenation of the relief by subsiding half-grabens and accompanying horst structures. During the Oberhof Formation, the Rotliegend volcanism of the Thüringer Wald region underwent a second culmination. Volcanic rocks alternate with alluvial and subordinately with lacustrine deposits. A mixed volcanic association of basic, intermediate and acid volcanics took place in the lower volcanic succession, whereas the upper parts of the Oberhof Formation are dominated by rhyolites. The Rotterode Formation, which has only been preserved in a few areas, consists of red sandstones with conglomeratic intercalations that enclose several rhyolitic bodies and tuff layers. The Tambach Formation starts with coarse conglomerates, which fill and cover a volcanic relief that had been partially dissected by canyons. The conglomerates pass upwards into red sandstones and sandy mudstones, which contain the youngest fossil beds of stratigraphic significance in the Thüringer Wald Rotliegend succession. The Elgersburg Formation has a lithology and age similar to the Tambach Formation, however it contains the last volcanic rocks of the Rotliegend section. The Eisenach Formation only occurs at the Western flank of the Ruhla Crystalline Complex and the adjacent Werra basin. The marginal facies is represented by interfingering of monotonous conglomeratic alluvial fan deposits and of red, silty to sandy mudstones that frequently display sedimentary structures of haloturbation. The mudstones are clearly dominant toward the basin center. The youngest Rotliegend sediments, the Neuenhof Formation, are overlain by the Kupferschiefer horizon marking the base of the Zechstein group. The sandy and conglomeratic sediments of the Neuenhof Formation are mainly fluvial deposits, which are reddish colored in their lower part at more marginal settings (Grenzkonglomerat). The upper part of the marginal deposits, as well as the entire formation in the center of the Werra Basin, is grey colored from seawater infiltration by the transgressing Zechstein Sea (Zechsteinkonglomerat). – The fossil content of the Rotliegend sediments permits a biostratigraphic zonation for several animal groups, including amphibians, conchostracans, blattid insects and freshwater sharks. Together with radiometric age determinations that span approximately 25 Ma, the biostratigraphic zonations and palaeoclimatic indicators correlate stratigraphically with other intramontane Rotliegend basins. – The sedimentary and volcanic history of the Stephanian – Rotliegend formations show a complex process of basin development in the Thüringer Wald district and adjacent areas. Tectonic control by NNESSW and N-S trending rift zones is under discussion for the Upper Stephanian volcanic formations. The basin setting for the Goldlauter and Oberhof Formations fits a dextral transtensional, pull-apart structure that was an integral part of the Thuringian-Franconian shear zone along the SW border of the Bohemian Massif. This transtensional regime possibly turned into a transpressive phase near the Oberhof\Rotterode boundary. The younger formations are distributed in more narrow depositional areas. The final phase of peneplane formation is poorly reflected by sediments; however Zechstein sedimentary patterns indicate that a residual palaeomorphologic relief was gradually covered by the Zechstein deposits.