In the Triassic, about 200 million years ago, the land sank again, forming the Germanic Basin in which the metre-thick layers of red sandstone could build up.

These were later covered over with layers of muschelkalk from a broad inland sea, then followed by sediments from the Late Triassic (or Keuper).

The bedrock here is composed of a number of different rocks, among them gneiss, granite, diorite, gabbro in the Frankenstein pluton, and so on.

At roughly the same time, the Central European plate began to tear apart so that the Upper Rhine Rift developed.

About 2500 BC, there is evidence that the Linear Pottery culture settled along the northern (Gersprenz) and southern (Neckar valley) edges of the Odenwald.

About AD 100, the older Odenwald line of the Neckar-Odenwald Limes was built under Roman Emperor Trajan (98-117).

The parts of the Odenwald farther in from the rivers, though, with their scant New Red Sandstone soils remained uninhabited.

Amorbach Monastery had the greatest importance for ecclesiastical, cultural and economic development in the eastern Odenwald.

The numerous Odenwald folk legends are mostly connected with historic geographic sites (castle, town, rock, road and so on) They relate: In some stories the local aspect firstly is connected with monsters (knight Georg fights against the man-eating lindworm near Frankenstein-castle) and creatures of nature with magic potency (a water spirit changed into a fox near Niedernhausen, the merwoman in the Meerwiese of Waldürn).

For example, there is explained: Beside these legends there are two famous and well-known Odenwaldsagas: In the Nibelungenlied (see also Nibelung) the dragon slayer Siegfried, on a hunting trip (instead of a failed campaign) leading from the Burgundian city of Worms into the Odenwald, is murdered by Hagen of Tronje.

Since no exact spot for this deed has been handed down, countless communities, especially in the Hessian Odenwald are squabbling over the right to call themselves “Siegfried’s Murder Site”, for example a spring near Gras-Ellenbach (Siegfriedsbrunnen), Mossautal-Hüttenthal Lindelbrunnen) or Heppenheim (Siegfriedbrunnen).

In times past the fortresses on the top of the Odenwald mountains controlled Bergstraße and the Weschnitz-, the Gersprenz-, the Mümling- and the Neckar-Valley.