The 12th-century Doppelkirche Schwarzrheindorf is a magnificent ‘double church’ where the nobility would sit on the upper level and peek down on the common parishioners through an octagonal opening in the floor. Considered one of the most beautiful Romanesque churches in Germany, its architecture is truly impressive, as is the restored Old Testament fresco cycle in the lower church.

　　The church is on the right bank of the Rhine in the suburb of Schwarzrheindorf, about 3km from the city centre.