St. Juliana Collegiate Church (Simultaneum Mosbach)

The history of Mosbach is to a large extent the history of the collegiate church. In the second half of the 14th century, the Benedictines, who lived together in a monastery, began building a collegiate church named after Saint Juliana. Its simple design is a typical example of late Gothic architecture in rural areas. In 1708, a dividing wall was built across the church so that Catholics and Protestants could use the church at the same time. In the Protestant part of the town church, several medieval gravestones (the oldest dates from 1312) and frescoes with German texts can be seen. An important work of art in the Catholic choir is the grave monument of Countess Palatine Johanna, who died in 1444, a bronze relief.

The Collegiate Church of St. Juliana is a "simultaneous church" in Mosbach. The evangelical part is called the collegiate church, the catholic part as the church of St. Juliana.
[de.wikipedia.org/wiki/Stiftskirche_St._Juliana_(Mosbach)]

As explanation:
Simultankirche, also Simultaneum or parity church, refers to a sacred building shared by several Christian denominations in denominational parity.

The collegiate church of St. Juliana is a simultaneous church in Mosbach in the Neckar-Odenwald district. The Protestant part is referred to as the collegiate church, the Catholic part as the Church of St. Juliana.