A behavior like "cat and mouse" is not only known in popular sayings: The disputes of castle lords from earlier years were equally reflected in their construction activities.
Thus, the castle known as Deuernburg "Mouse" is ultimately a counter-castle to the castle "Cat" in the conflict between the Counts of Katzenelnbogen and Kurtrier. Castle "Mouse" was established in 1356 by Archbishop Boemund II of Trier in St. Goarshausen-Wellmich - and was from the very beginning directed against the upstream Rhinefels, a castle of the aforementioned Counts of Katzenelnbogen. They did not tolerate the threat to their toll processing in St. Goar from the new Deuernburg on the opposite bank of the Rhine for long and completed their castle Neu-Katzenelnbogen - later called Castle "Cat" - as a hostile response before 1371. The two fortresses together count among the most famous sights in the Rhine Valley. In contrast to the "enemy castle Cat," the "Mouse," with its core structure rebuilt since 1900, conveys an impression of medieval castle construction.

The castle is privately owned.