On the ramparts and forts three hundred cannon, for the most part supplied by the city of Nuremberg, were placed in position.

As the camp between the ramparts and the town was traversed by the river Pegnitz numerous bridges were thrown across it, so that the whole force could concentrate on either side in case of attack.

So vigorously did the army, assisted by the citizens, labour at these works, that they were completed in fourteen days after Gustavus reached Nuremberg.
It was on the 19th of June that the Swedish army arrived there, and on the 30th Wallenstein and Maximilian of Bavaria appeared before it with the intention of making an immediate assault.

The works, however, although not yet quite completed, were so formidable that Wallenstein saw at once that the success of an assault upon them would be extremely doubtful, and, in spite of the earnest entreaties of Maximilian to lead his army to the assault, he decided to reduce the place by starvation.
This method appeared at once easy and certain.

The whole of the surrounding country belonged to the Bishop of Bamberg, who was devoted to the Imperialist cause, and he possessed all the towns, and strong places in the circle of country around Nuremberg.