The "Salzburger Stier" at the Hohensalzburg Fortress is a mechanical organ instrument known as a hornwerk, originally built by Michael Rytzinger in 1502. It comprised a wind chest, bellows, and pipes that produced a powerful triad when the bellows were activated. Such instruments were typically installed in medieval city and monastery fortifications within special horn towers, serving siren-like functions to signal the beginning and end of the workday to the populace. The instrument was restored in 1893 by Matthaeus Mauracher and again in 2002 by Ferdinand Salomon.

Additionals:

https://organindex.de/index.php?title=Salzburg,_Salzburger_Stier_(Hornwerk)