Asterstein Fort, Military fortress in Koblenz, Germany

Asterstein Fort is a Prussian defensive structure built on the Pfaffendorfer Heights above the south bank of the Rhine near Koblenz. The site has a central reduit, an original gate structure, and preserved casemates that together show how the defensive layers were organized.

Prussian engineers built the fort between 1819 and 1826 as the main work of the Pfaffendorfer Höhe system, after deciding against reusing older French earthworks from the siege of Ehrenbreitstein. Troops first occupied it in 1830, and in 1847 it was named after General Ernst Ludwig von Aster. In 1865 the rampart was extended northeast to create a second front, and the left flank tower was demolished in 1875.

The fort was named in 1847 after General Ernst Ludwig von Aster, inspector of Prussian fortresses in the Rhineland during the construction of the Koblenz defences. The name passed to the surrounding Koblenz district of Asterstein. Since 2019 the Festungspark laid out around the fort has linked it with the monument to the fallen of the VIII Army Corps from the 1866 war.

Access to the fort is arranged through guided visits run by local volunteers, and booking ahead is needed. Checking the organizers' website before your visit helps you find open dates and get a sense of what the tour covers.

The reduit housed a newspaper press from 1941: first the Nazi Nationalblatt until 1945, then the Rhein-Zeitung until 1951. After that, Koblenz families lived in the fort until 1971, when it was abandoned and its stairs and wooden ceilings were destroyed to prevent illegal resettlement.