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For the village in Crete, see Oreino, Lasithi.
Municipal unit in Greece
Oreino (Greek: Ορεινό) is a former municipality in the Kavala regional unit, East Macedonia and Thrace, Greece. Since the 2011 local government reform it is part of the municipality Nestos, of which it is a municipal unit. The municipal unit has an area of 318.555 km. Population 960 (2021). The seat of the municipality was in Lekani.