The column commemorating King Sigismund III of Poland (a work by Clemente Molli, erected in 1644) is the oldest and one of the symbolic landmarks of the city and the first secular monument in the form of a column in modern history. On the east side of the square stands the Royal Castle reconstructed after the devastation of World War II. It was formerly the residence of the dukes of Mazovia, and then of the Polish kings and grand dukes of Lithuania from the 16th to 18th centuries. The Germans bombed and blew it up in the beginning of World War II (September 1939), and then it was completely destroyed in 1944–1945 (see picture below).