Ormenio is the northernmost place in all of Greece. It is part of the municipal unit of Trigono in the Evros regional unit of Thrace. It is situated near the right bank of the river Evros, which forms the border with Bulgaria here. On the other side of the Evros, 6 km to the north, lies the Bulgarian town Svilengrad. Nearby villages in Greece are Ptelea to its southeast and Petrota to its southwest. Ormenio is bypassed by the Greek National Road 51/ European route E85 (Feres - Soufli - Orestiada - Ormenio), which continues across the border as the Bulgarian road 80 to Svilengrad. Ormenio had a railway station on the line from Didymoteicho to Harmanli in Bulgaria. During the Ottoman era, Ormenio was called Çirmen in Turkish.