Neo Gynaikokastro (Greek: Νέο Γυναικόκαστρο, old name: Avret Hişar)[2] is a village in the Kilkis region of Greece.

[a] The highest point in the vicinity is 188 metres above sea level, 1.6 km north of Neo Gynaikokastro.

[2] During the years of Ottoman rule there was the kaza of Avret Hişar that belonged to the Salonica Vilayet.

This area of the Macedonian front was the scene of fighting between the Bulgarians and the Entente forces dominated by the Armée d'Orient (1915–1919).

[10] Its current inhabitants are descended from Greek refugees who came from the "Tsataltza" province of Istanbul and the "Artohan" region of the Caucasus.