Namur was garrisoned by about troops and infantry of the Belgian 4th Division under the command of General Augustin Michel.
After a reconnaissance on 19 August, Gallwitz decided that a was impossible and chose to attack the north-eastern front of the fortress with the 3rd Guard Division between Hingeon and Vezin and the eastern side by the XI Corps, with the 1st Guard Reserve Division in reserve at Andenne.