An exceptional, briefly exposed section across the boundary between the Pieniny Klippen Belt (PKB) and the Central Carpathian Paleogene Basin (CCPB) in Eastern Slovakia showed that the contact is formed by a single, subvertical fault plane. Whereas the Oligocene CCPB deposits exhibit only weak deformation with S-verging fold-and-thrust structures, the Cretaceous PKB sediments are internally strongly sheared with scaly fabric and numerous calcite veins. It is inferred that the PKB suffered strong thrusting- and wrenching-related deformation in pre-Oligocene times, while the Early Miocene oblique backthrusting resulted in exhumation of the PKB and formation of its steep fault boundaries.