The Palace of the Parliament is the heaviest building in the world and the second largest administrative building after the Pentagon. Commissioned by dictator Nicolae Ceausescu and built between 1984-1997, this massive structure covers 365,000 square meters with over 1,000 rooms across 12 floors and 8 underground levels. Built at enormous human and financial cost (entire historic neighborhoods were demolished), it now houses the Romanian Parliament and a contemporary art museum. Visitors can explore the opulent interior featuring Romanian marble, crystal chandeliers, and intricate woodwork through guided tours only.