The mansion was built in the beginning of the 1900s as a private residence for Kostaki Teophylaktos, a notable banker of Greek origin.

[2] The Kostaki Mansion was assigned in 1937 to the Ministry of National Education, and was used for fifty years long as a vocational high school for girls.

[2] In this section, old coins and a wide range of items are exhibited, among them of marble, basalt, ceramic, metal and glas from Bronze Age (3300–1200 BCE), Classic period (480–323 BC), Hellenistic (323-146 BC), Roman and Byzantine periods.

[2] The ground floor is prepared to show the architecture of the building and history of the mansion in chronological order.

[4] The walls of all the rooms are decorated with near Baroque style hand carved ornamental works.