The area is a large karst plateau with steep sides, and several mountain peaks above 2000 m. The highest point is the summit of Großer Priel, at 2,515 metres (8,251 ft).

One position claims this comes from the range being the largest karst plateau of the Limestone Alps, featuring many lakes, caves, and sinkholes.

The range contains an arid plateau, steep cliffs on the Styria-facing side, and extensive karst formations, including hundreds of caves, gorges, crevices, and shafts.

The Schönberg Cave in the western part of the range is the longest in the Eastern Alps, extending an impressive 135 km (84 mi) long and reaching a depth of 1,061 m (3,481 ft).

A few large lakes, such as the Grundlesee and the Altausseer See, sit in the mountain’s southwest basin, where the Traun Glacier once existed during previous Ice Ages.

Totes Gebirge contains over 600 caves, enormous gorges, and crevices that move water from higher elevations to the valleys and lowlands below.

Around this time, Pangea began to split along the Eurasian and African plates, creating a shallow seaway known as the Tethys Sea, where sediment and shells collected on the ocean floor.

During the early Cretaceous era, around 140 million years ago, the African plate drifted north, pushing sediment and folding deposits on the ocean floor over each other.