'Wetter meadow') is a fertile undulating tract, watered by the Wetter,[1] a tributary of the Nidda River, in the western German state of Hesse, between the hilly province Oberhessen and the north-western Taunus mountains.
The Wetterau is located north of Frankfurt am Main, on the eastern side of the Taunus and south-west of the Vogelsberg.
After the end of the Germanic and Gallic wars (58 to 51 BC) a number of Roman forts and roads were built in the Wetterau.
The economic power of the Wetterau has increased continuously through specific promotion of its urban centres Frankfurt am Main, Wetzlar, Gelnhausen and Friedberg since Frederick I, Holy Roman Emperor.
Since 1422 the late medieval policy initially led to establishment of the estates of the realm, the alliance of knights, and lords and counts of the Wetterau.