The arcuate orogen of the Aegean Arc resulted from a continuous northward subduction of the African plate below the southern margin of Eurasia during the Cretaceous and the entire Cenozoic. The External Hellenides, the frontal part of the Arc, is a nappe pile representing of basinal and carbonate platforms palaeogeographic domains which were stacked during the Late Oligocene – Early Miocene. In Peloponnese and Crete syn-convergence exhumation formed low-angle normal faults that separate high‐pressure rocks in their footwall from non‐metamorphosed rocks in the hanging wall while a younger episode of high-angle normal faulting formed a series of tectonic grabens filled mainly by terrestrial sediments.

Peloponnesus offers very good sections of those late Cenozoic extensional episodes and of the transition of the Upper Oligocene – Lower Miocene fold-and-thrust-belt to the extensional domains. So, in this contribution the following topics will be described and discussed:

a) Stratigraphy, age, structure and metamorphism for each of the tectonic units.

b) The geometry and kinematics of the extensional structures and their implications for the emplacement of the upper nappes onto the lower ones.

c) The high-angle normal faulting and the evolution of the related extensional basins.

d) The tectonic stress regime during the Quaternary.

e) A reconstruction of the possible geometry of this part of the Aegean Arc.