With a flow length of 527 kilometers, the Main is the longest right-hand tributary of the Rhine.
The source rivers of the Main have their source in the Fichtelgebirge (White Main) and in the Franconian Jura (Red Main).
On the western edge of the town of Kulmbach in the district of Melkendorf near Steinenhausen Castle, the two source rivers unite to form the actual Main.
Despite many striking changes in direction, the river course keeps its main flow direction from east to west - which is rare in Central Europe - and touches several Franconian low mountain ranges. Large parts of the Franconian wine-growing region and numerous, partly well-preserved historical town centers are located on the Main.
The Main flows through large conurbations around Würzburg and Frankfurt.
Opposite the old town of Mainz - between Ginsheim-Gustavsburg and the Maaraue in Mainz-Kostheim - it flows into the Rhine.
From there (km 0) upstream to above the railway bridge near Hallstadt (km 387.69) is the Main (Ma) federal waterway.
The Main is not exceptionally long, but it is nonetheless a historically and geographically important river.
In late antiquity, its lower reaches between Miltenberg and Großkrotzenburg formed a short section of the outer border of the province of Upper Germany of the Roman Empire.
In the 19th century, the Main line separated the spheres of influence of the two major German powers, Austria and Prussia, within the German Confederation, with its headquarters in Frankfurt, directly on the Main.
The Main, which actually runs within Upper Germany, is neither a dialect nor a cultural border, but according to common understanding, the Main line divides Germany into a northern and southern part.
In terms of transport geography, the Rhine-Main area is the center of Germany and Europe.
(Source: Wikipedia)