The center of the square formerly ran along Szeroka Street, also known as Żydowska Street - the center of Jewish life in Lublin, where more than a dozen synagogues and houses of prayer were located. A richly detailed historical guide to Lublin's Jewish quarter, "Die Judenstadt von Lublin" (ed. Berlin, 1919) was created by Majer Balaban (1877-1942), a distinguished historian, later founder of the Institute of Judaic Studies in Warsaw, who served in Lublin during World War I as an officer - field rabbi of the Austrian army. Balaban described, among other things, the Kotlari Synagogue, located at the beginning of Szeroka Street - and thus also near the entrance to Castle Square - located on the first floor of a tenement house at 2 Szeroka Street, founded in 1638 by Hirsz Doktorowicz, the court factor of King Wladyslaw IV. Opposite, at 3 Szeroka Street, was the house of prayer of trade officials, called Mszorsimszul.