The grand Alte Synagoge served as the hub of Essen's Jewish community between 1913 and 1938 and miraculously survived WWII largely intact. A memorial site since 1980, it now harbours the House of Jewish Culture with exhibits, concerts and discussions. A free audioguide (also in English) provides useful background information.
You can learn about Jewish traditions and festivals as well as the history of the synagogue and the local Jewish community.