The second main part of the book “Neu-Tripumphierende Fortification auff allerley Situationen/ defensivè und offensivè zu gebrauchen” deals with the concept of the disposition of the citadel and the fortification of the city. In three books it explains which rules and principles must be followed when planning the fortification of a city and a citadel.
The citadel fulfills the following functions: It represents the last place of retreat for the soldiers and the government when the enemy invades. Moreover, it is a symbol of authority, it shows military strength to the population.
There are three different compositions of city and citadel: the citadel is located in the middle, on the edge or outside the city. The first basic rule is that the fortification of the city wall should have at least twice as many corners as that of the citadel. It is also stated that the citadel should be built with stronger, higher walls than the city walls. It is also important that the citadel has an open space in the direction of the city, where troops can be positioned or victory marches can be conducted. The construction of the citadel must also take into account the political situation or the relationship between the authorities and the population, especially in the interior. If the people are not loyal, additional protection against the own population must be provided.
The book explains which topographical conditions should be used and how. The citadel should ideally be built on the highest and hardest rock. Open areas in front of the city wall are more suitable than obscure mountains, as this takes away the possibility for the enemy to hide or tunnel unseen. On the one hand, the entrance to the citadel should be large enough to be suitable for everyday use. On the other hand, it should be as narrow as possible so as not to give the enemy an advantage in the event of an attack.
Depending on the geographical location of the city, various aspects must be taken into account: If the city is located on an island in the sea or in a lake, ships should not be able to approach the city or citadel, if possible. The shore should be out of range, and the water should not freeze solid in winter. A city on a river island should ideally be elongated, with the citadel at the top and the city at the bottom of the island. To ensure that the island does not flood, the island should ideally be very rocky. If a river flows through the city, the two parts should be connected by a bridge that is controlled on both sides. If streams penetrate the city walls, you must know exactly how they behave so that the enemy cannot take advantage of them.
Keywords: citadel, topography, composition