In the late 18th century, after the fall of the Polish–Lithuanian Commonwealth, several families lived in parts of the ruined palace. Soon after the Grand Duchy of Lithuania was incorporated into the Russian Empire, officials ordered the demolition of the remaining sections of the palace. The structure was almost completely demolished in 1801, the bricks and stones were sold, and the site was bowered. Only a small portion of the walls up to the second floor in the eastern wing survived, that were sold to the Jewish merchant Abraham Schlossberg around 1800, who incorporated them into his house. After the November uprising of 1831, Schlossberg's house had been bought and taken over by Imperial Russian Army, which had presence in arsenals nearby. As Vilnius fortress was established, the building became part of the fortress, which by itself was surrounded by the ditch. The Schlossberg's house in 1840 Vilnius map is named as barracks (). By the end of 19th century the fortress' ditch on former palace's site was covered with soil and turned into the city's park. After Lithuania regained its independence following World War I in 1918, the Schlossberg's house became the headquarters of the army. It soon was captured by Polish troops following the Polish annexation of Vilnius. During World War II, it was the office of the German Wehrmacht, and after World War II it was used by Soviet security structures and later transformed into a Respublican Pioneers Palace. Pioneers' organisation vacated the building by the 1987. Archeological excavations started on the site, because Schlossberg's house was proposed for the People's Friendship Museum and for this conversion architectural investigation were needed to take place. Sporadic archeological excavations took place already in 1964, when works for installation of central heating system in Schlossberg's house has been undertaken. After the fall of the Iron Curtain in 1989, Lithuania became independent again. In 1994 archeological excavations were put on hold due lack of funding. In 1994 Lithuanian Institute of History established Castles' Investigation Group that supervised archeological excavations. Schlossberg's house was used as Group's headquarters and housed collection of archaeological material found on the site. By the end of 1980s archeological excavations covered more and more territory, exposure of excavated basements to environmental factors (e. g. weather) led to decay of the materials (in particular, wooden structures and bricks). To solve this problem, it was decided in 1988 to erect temporary buildings – greenhouses (also as known as "hangars" due to their brownish colour and shape of these buildings).