Located atop Dealul Spirii, also known as Arsenal Hill, the Palace of the Parliament, originally called the People's Palace, is the seat of the Parliament of Romania and an essential piece of Romanian history, the most spectacular Romanian project carried out under the dictatorship of Communist leader Nicolae Ceaușescu. Constructed over a period of 13 years, between 1984 and 1997, in Socialist realist and modernist neoclassical architectural forms and styles, it is the largest administrative building in the world, dominating the landscape of the city with a height of 276 feet (84 m). The 788 feet (240 m) long, 886 feet (270 m) wide massive building, covering a floor area of 3,930,000 sq feet (365,000 sq m), is the world's third-largest building, after the Pentagon in the United States and the Sappaya-Sapasathan in Thailand.

Shortly after the devastating earthquake in 1977, Nicolae Ceauşescu initiated the plan to build a new political-administrative centre in Bucharest, as a consequence of the urbanization campaign, influenced by his friendship with the North Korean leader, Kim Il-Sung. Starting in 1980, around 5% area of Bucharest, almost equivalent to the total surface of Venice, was demolished to mark the end of the old narrow streets, paved with cubic stone, along with the old and quaint Romanian houses with bohemian glamour. People were served eviction notices in the morning to pack up and leave and by noon the bulldozers arrived, starting to demolish everything in sight. In addition to that, the Brâncovenesc Hospital, the first forensic medicine institute in the world, was demolished, 20 churches were destroyed, including a monastery dating back to 1564, 8 were moved, 10,000 homes were demolished and over 57,000 families were evicted. For the construction of the Palace of the Parliament, meant to symbolize the triumph of communism in Romania and an emblematic home of the Ceausescu family, more than 100,000 workers were engaged, more than 20,000 persons worked 24 hours three shifts per day, even 12,000 soldiers also took part in the construction works between 1984 and 1990 and it is estimated that around 3,000 of them died in the process.

Initiated by Nicolae Ceauşescu, the second of two long-ruling heads of state in the country since WW II and designed and supervised by the 28-year-old chief architect Mira Anca Victoria Mărculeț Petrescu with her team of approximately 700 architects, the Palace of the Parliament was constructed with materials produced in Romania, which included 1,000,000 cubic metres of marble, 1,000 tons of basalt and 900,000 cubic metres of rich wood. But probably the hardest job that the architects had to face, was to explain the details of the plan to the Ceaușescu couple, who had no idea about the matter, but used to inspect the job by walking over the models on a rolling bridge, giving undue instructions and changing plans every seven days. The Palace of Parliament, considered the pinnacle of communist architecture in Romania with its opulence and ostentatious décor, was built to reflect the prosperity and grandeur of the multilateral society. However, the name of the building is cruelly ironic, because when the common people of the country were facing food shortages, blackouts and gas cuts, two billion dollars were freely invested for the completion of the massive project, dedicated to its ruling class. Demolition of the incomplete building was on the cards at the onset of the Revolution in 1989, as the people were resentful about the symbols of the past era, but finally, it was decided to complete the construction, as it was found to be cheaper than demolishing it and the building was completed between 1992 and 1996. Eventually, the events of December 1989, culminating with the fall of the communist regime, changed the purpose of the People's House, when from a palace meant for a dictator-president, it became the seat of the new democratic government. Today, the Palace of the Parliament serves exclusively as an administrative building and hosts the Parliament of Romania, along with its Chamber of Deputies, the Palace of the Chamber of Deputies and the Romanian Senate.

Equipped with about 1000 rooms of which 440 are offices, more than 30 ballrooms, 4 restaurants, 3 libraries, 2 underground parking lots, 1 big concert room, 1 unfinished pool and thousands of square metres used for other purposes, the impressive building of the Palace of the Parliament also houses one of the most important art museums in Bucharest, the National Museum of Contemporary Art since 2004.The huge nine storey building also has eight underground levels, as Ceaușescu was apprehensive of nuclear war, complete with 20 km of secret tunnels, leading to other main government buildings. While the underground levels have several residential apartments for state leadership, to be used in the event of war, the bunker, equipped with direct telephone communication with all the military units in Romania, is made of thick concrete walls, said to be impervious to radiation.

Among the several well decorated halls, the Human Rights Hall is one of the most impressive halls, projected to hold the meetings of the Executive Political Committee of the Communist Party and has a huge round table, 60 identical chairs for the Executive Political Committee members and the second-largest chandelier in the Palace of Parliament. The pink coloured Nicolae Titulescu Hall is currently used by the President of the Chamber of Deputies and the President of the Senate during official meetings. The Tache Ionescu Hall, named after Tache Ionescu, a Romanian politician, journalist, lawyer and diplomat, who also enjoyed a reputation as a short story author, is devoid of natural light, but illuminated by 12 chandeliers, which highlights the beauty of the columns that support it. The hall with its ceiling decorated with gold leaves, is equipped with special acoustics, where even the whispers are echoed and the applause becomes louder by the echo. The Union Hall, measuring 2200 sq m, is the largest hall in the building and its carpet, weighing 3 tons, was woven directly inside the room, being too big to be transported. The Alexandru Ioan Cuza Hall has a balcony, from where Michael Jackson in 1992, wrongly addressed his fans Hello, Budapest, instead of Hello, Bucharest, although he was not the only person to confuse the names of the two capitals.

Located in the city centre, the impressive building of the Palace of Parliament, a reminder of the old communist regime, has now become one of the most visited tourist attractions in Bucharest. A glass annexe was built alongside the external elevators of the palace between 2003 and 2004, to facilitate outside access to the National Museum of Contemporary Art, which was opened in 2004 in the west wing of the building. Today, although the massive building is used by different state institutions and international bodies for events like conferences and symposia, almost 70% of the building remains empty most of the time. However, considered the heaviest building in the world, weighing about 4,098,500,000 kilograms, the Palace of the Parliament sinks 6 mm (0.24 in) each year due to its weight, as its massive weight is causing the layers of sediment below the building to settle.