The Rift of Corinth is a major intra-continental rift controlled by a Pleistocene and still active detachment fault. Its hangingwall contains normal faults which have migrated as evidenced by geomorphologic studies and by the geometrical relations of the sedimentary series that they controlled successively. However, because of the lack of paleontological data in the continental synrift sediments, the timing of this migration is unknown. Therefore, we attempted to date directly the faults using the U/Th method on calcite crystallizations. Preliminary results reveal that this method may be a useful tool in neotectonics. In this first attempt, we studied the Xylokastro-Loutro fault and the Valimi fault. The age obtained on post-tectonic calcite of the first fault shows that it locked at least 112.4¿0.4 ka ago. Syntectonic calcite of the Valimi fault yields an age of 382.0¿31.1 ka, showing that the fault was still active at that time. Tectonic implications of these results are discussed. ¿ 2001 American Geophysical Union