The temple of Agios Dimitrianos was built in the early 19th century and is located in the center of Flassou village, among its traditional houses. The church is a one-aisled basilica, which is covered in a simplified form of arched arches and crosses. Its size is considerably larger than the churches of the Turkish domination, but also significantly smaller than Gothic monuments. It has a towering bell tower with three electronic bells and another one for emergency.

The bell tower is located south of the sanctuary and adjoins the entire building. The church interior is adorned with an exceptional art, wood-carved iconostasis, framed with old icons, a despotic throne, a pulpit and a pilgrim, all preserved in excellent condition. The icon wall is at the western entrance of the temple and carries a small icon of Saint Dimitrianos. The large double-sided icon with face of the saint is on the iconostasis. Saint Dimitrianos is celebrated on the 6th of November, where the veneration of his holy image takes place.