Alsgasse (Dornbach), named in 1877 after the Alser Bach, a 10.55-kilometre-long river that is now largely run as a brook canal. The first documented mention comes from the year 1044. There are various possible derivations for the name Als. The name is often derived from the Celtic Alt, which can mean stream or cool stream. According to other interpretations, the name could also come from the Old Church Slavonic word Olsa, which is translated as alder.