The Main is navigable for shipping from its mouth at the Rhine close to Mainz for to
Bamberg. Since 1992, the Main has been connected to the Danube via the
Rhine-Main-Danube Canal and the highly regulated
Altmühl river. The Main has been canalized with 34 large locks () to allow
CEMT class V vessels () to navigate the total length of the river. The 16 locks in the adjacent Rhine-Main-Danube Canal and the Danube itself are of the same dimensions.
Weirs and locks There are 34
weirs and
locks along the 380 km navigable portion of the Main, from the confluence with the Regnitz near Bamberg, to the Rhine. •
No.: Number of the lock (from upstream to downstream). •
Name: Name of the lock. •
Location: City or town where the lock is located. •
Year built: Year when the lock was put into operation (replacement dates are also listed where applicable). •
Main-km: Location on the Main, measured from the 0 km stone in Mainz-Kostheim. The reference point is the center of the lock or lock group. •
Distance between locks: length in km of impoundment (between adjacent locks). •
Altitude: Height in meters above mean sea level of the upper water at normal levels. •
Height: Height of the dam in meters (the height of the Kostheim lock depends on the water level of the Rhine). •
Lock length: Usable length of the lock chamber in meters. •
Lock width: Usable width of the lock chamber in meters.
Hydroelectric power generation Most of the weirs or dams along the Main also have turbines for power generation. •
No.: Number of the dam/weir (from upstream to downstream). •
Name: Name of the dam/weir. •
Height: Height of the dam/weir in meters (the height of the Kostheim dam depends on the water level of the Rhine). •
Power: Maximum power generation capacity in megawatts. •
Turbines: Type and number of turbines. •
Operator: Operator of the hydroelectric plant. ==Tributaries==