The building housing the Islamic Parliament of Iran used to be the Senate established under Pahlavi II. It was built between 1953 and 1958 in the northern section of Sepah Street (today Imam Khomeini St.) of Tehran. The building was reserved for the Iranian Senate meetings. Before this building was built the Senate held its sessions in the building of the National Consultative Assembly.
After the dissolution of the Assembly in 1952 and its reestablishment a year later, the Senators decided to find a specific place for their sessions. Backed by Shah Mohammad Reza Pahlavi, the Senators purchased the Palace of Ali-Reza Pahlavi (the Shah's brother) and reserved it for the Senate. From March 1955 onwards, the Senate sessions were held there. However, since the former palace had not been designed for administrative purposes, library, and other formalities, a new building was decided to be built in its vicinity. Until the 1979 Islamic Revolution, Senate sessions were held in this building.
In the aftermath of the Islamic Revolution, the building turned into a place for the Assembly of Experts of Constitution which was tasked with drafting a Constitution for the Islamic Republic of Iran. After that, it was given to the Islamic Parliament of Iran that held its open sessions there until 2001. After the new building was built for the Islamic Parliament, the former Senate building was used only for official ceremonies and the annual gatherings of the Assembly of Experts of Supreme Leadership.
The Senate building was designed by Heydar Ghiabi and Mohsen Foroughi, who had modeled it based on the European Senate buildings. The Senate building is more than 320 centimeters tall, sprawling on 16,000 square meters with a built-up area of 6,000 square meters. The exterior of the building is adorned with a total 10,000 square meters of marble stones. The building is fitted with several apartments for welcoming guests.
The most outstanding feature of this building is the staircase built in front of this palace, which is reminiscent of Achaemenid palaces. What is marked in this building is its central integration, leading every visitor to a modular network of squares of identical size. There are a total of 117 such squares, five of which are distinguished at the entrance of the building.
The harmony and homogeneity of the palace are seen when we look at the chain-shaped metal columns of both sides and the two square-shaped ceilings in the same perspective. The chains seen from that perspective are indicative of justice and democracy. A homogenous perspective frames the palace while offering a modernist architecture view to local and historical decoration.
In the interior architecture of this building, by using circular shapes, a big entry has been built so as to show the ancient Iranian architecture.