Krasiński Palace. Built 1677-1693 for Jan Dobrogost Krasiński in baroque style by Tylman Van Gameren. The building's facade features sculptures by Andreas Schlüter. The decorations inside the building were designed in the 1780s by Domenico Merlini.

Called Palace of the Commonwealth. Twice restored 1765-1795. Seat of Supreme Court 1815-1831 and again 1918-1939. Burnt down in 1944. Rebuilt 1948-1961.

Today it is a part of the Polish National Library's Special Collections Section (Manuscripts and Old Prints) from the Załuski Library (only 5% of former rich collection located in the palace).