Trzech Krzyży Square. The St. Alexander church.
The church was built in the years 1818-1826.
During the Warsaw Uprising, i.e. in the beginning of September 1944 German planes threw nine bombs on the church. Consequently, its dome, the main nave, the whole side walls and the right tower collapsed.
The church was reconstructed in the years 1949-1952.

On the church wall there are the following plaques:
- commemorating the soldiers of the companies commanded by "Bradl", "Reda", and "Ziuk" from the battalion "Miłosz" of the 72nd infantry regiment of the Home Army 28th division, who fell in the Warsaw Uprising in the Southern Śródmieście (City Centre);
- commemorating the Home Army battalion "Bełt", fallen during both the occupation and the Warsaw Uprising;
- commemorating the soldiers from the assault battalion "Sokół" of the Home Army unit "Sarna";
- in memory of "Zawiszacy", the youngest scouts of the Grey Regiments; on September 2, 1944 Zawiszacy took part in the rescue action after Germans had bombarded the St. Alexander church.