The Tower Triva (Werk 104) is located in the inner fortress ring
Museum
Fortress Ingolstadt-Tower Triva (Werk 104)

The Triva Tower, also known as Work 104, is a component of the former Ingolstadt State Fortress. This neoclassical fortress is named after the Bavarian General and Minister of War Johann Nepomuk von Triva.
History+
The Triva Tower was constructed between 1828 and 1841 in a circular style as the eastern flank tower of the Reduit Tilly. Its exterior design was influenced by Leo von Klenze. Originally designed to repel attackers with its 58 gun casemates on two levels, the elongated oval fortress with an inner courtyard and walls up to four meters thick was converted into a barracks between 1889 and 1890. After World War II, the tower served as emergency accommodation for displaced persons and refugees, later housing vocational training centers and various commercial businesses.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 48.7624, 11.4353