Abstract: Crustal extension directions trending NNE-SSW and NW-SE to NNW-SSE are documented at the southeasternboundary of the Galatean Volcanic Province (GVP), located at the NW central Anatolia, and at the north of theAegean Region, in Turkey. Extension affects a continental volcano-sedimentary sequence deposited between theEarly Miocene to Pliocene (?) time. Field observations suggest syntectonic volcanism and sedimentation, andextension may begin in the Early-Middle Miocene time. Similar Miocene crustal extension directions are known fromthe Aegean Region. Both zones have also comparable Miocene magmatic evolutions, characterized by production ofLower-Middle Miocene calc-alkalic and Upper Miocene alkalic magmas.The GVP is presently bounded at the north by the North Anatolian fault (NAF), the most important active fracturezone of the Anatolian block. The stress fields associated with the GVP extensions and the NAF movements clearlyare different. This implies that the GVP extensional regime must have ended prior to the NAF initiation at the EarlyPliocene.Based on the structural and magmatic similarities, we propose that the Aegean and GVP zones were parts of thesame block, during possibly much of the Miocene, until the Early Pliocene NAF inception.