It is formed almost entirely of a succession of sandstones and shales of Cretaceous and Tertiary age - the so-called Carpathian Sandstone - and these are thrown into a series of isoclinal folds dipping constantly to the south.
Of all the peculiar features of the Carpathian chain, perhaps the most remarkable is the fringe of volcanic rocks which lies along its inner margin.
The Bogomil propaganda follows the mountain chains of central Europe, starting from the Balkans and continuing along the Carpathian Mountains, the Alps and the Pyrenees, with' ramifications north and south (Germany, England and Spain).
It consists of a marble statue of Austria erected on a pedestal of green Carpathian sandstone.
In the space which is thus enclosed, lies the Tertiary basin of the Hungarian plain; and outside the belt, on the northern side, is a region which, geologically, is composite, but has uniformly resisted the Carpathian folding.