The geological origins of the area of the land of Cortona is essentially brought back from the lower Miocene, upper Pliocene and Miocene periods.  From a lithological point of view, the territory is characterised by sandstone, marl and shale, with fluvio-lacustrine deposits, of clay and layers of debris.

Typically suitable for the cultivation of vines are the ancient fluvial and alluvial terraces, as well as those that join the areas between peaks and flat levels.  As such, the slightly calcareous territory presents an optimal equilibrium with respect to the granulometric fractions, which form part of clay, lime, fine or coarse sand.