UNESCO WHS the Semmering-Railway has uncontested a very
important status under the world's mountain railways:
It is the first one which crossed a high-mountains area
and counts therefore as the prototype of railway lines
rich of bridges and tunnel as well as a symbol of taming the nature.

Although the distance between the Semmering railway ending stations
Gloggnitz (Lower Austria/Niederösterreich) and Mürzzuschlag (Styria/Steiermark)
is only 21 km in air line, the railway has to do through the mountainous
landscape nearly the double distance of 41,7 km and the difference in altitude of 439 m.