The palace was built in 1976 as the Kumsusan Assembly Hall and served as Kim Il-sung's official residence. Following the elder Kim's death in 1994, Kim Jong-il had the building renovated and transformed into his father's mausoleum. It is believed that the conversion cost at least $100 million. Some sources put the figure as high as $900 million. Inside the palace, Kim Il-sung's embalmed body lies inside a clear glass sarcophagus. His head rests on a Korean-style pillow and he is covered by the flag of the Workers' Party of Korea. Kim Jong-il is now on display in a room close to his father's remains and positioned in a very similar way.