Mostviertel (English:
Must Quarter) is the southwestern quarter of the four quarters of
Lower Austria (the northeast state of the 9 states in
Austria). It is bordered on the north by the
Danube and to the south and west by the state borders of
Styria and
Upper Austria respectively. The
Wienerwald forms the natural border to the east and gives the quarter its second name, "The Quarter Over the Wienerwald".