In response to Napoleonic forces, the Prussian government added yet another fortress barrier. The invincible Vistulamouth Fortress lost its military significance in 1919, along with smaller forts along the river, most of which were pulled down. It was severely damaged in 1945 and partially rebuilt. Today, the fortress is a virtual oasis amid the vast industrial sprawl of a chemical factory. Sulphur and coal emissions are ever-present.
Waves created by large passing ships also weaken the foundation.
An American Express grant was awarded to the site in 1998 for initial restoration work, but additional, detailed studies are needed to determine how to save the site, literally and contextually. Listed in 1998, 2000.