The area in which the square was going to be built was intended to be used for the construction of the palace (anaktora) by architects Stamatios Kleanthis and Eduard Schaubert.

Omonoia Square was a center where people met and social life thrived, as it was also the railway's starting point, surrounded by numerous hotels.

Omonoia Square became circular and marble bars were put at the entrances of the underground railway station.

The fountain of Omonia became a famous city landmark and the square itself was depicted many times in Greek movies of the period.

In November 1992, the fountain and the sculpture "Runner" were destroyed in order to excavate the area for the construction of the new red line of the Athens Metro and the new station.

[2] From mid-2019 to February 2020, the square underwent yet another major reconstruction, which became necessary after previous aesthetic and urban changes had eventually led to the degradation of this central and historical area of Athens.

Sporting celebrations have been held at the square, including following Greece's victory in the EuroBasket 2005 finals and in winning the championship.

After its transformation in 2003, the square lost some of its former value and prestige, but nevertheless continues to represent a multicultural place and point of communication as a transportation hub for thousands throughout the day.