A representative sample of the early period of Neoclassicism in Greece, the building is an abstemious work of strict geometry in its mass. Doric-style column rows stand in front of the facade and the back (eastern) side.
It was built between 1836 and 1840. Originally it served as a palace of Otho, the first King of Greece after the end of the Turkish occupation, who moved from Nauplion to Athens in 1834. The expenses of its construction were carried out by Otho's father, King Ludwig of Bavaria, who financed the project as a personal loan to his son. The Greek state expropriated the estates occupied by the building, the front plaza and the royal garden. The first Parliament was temporarily housed in a private residence building in Kolokotronis Street and afterwards it moved to the University building and much later, in 1857, to the building of Stadiou Street that houses today the Museum of History and Ethnography.
Today, it serves still as the seat of the Hellenic Parliament and houses offices, the National Assembly Room, the office of the president of the Assembly, the Archives and other services.