Question: In which year was this military base established that functioned as a World War II armament storage depot and is located near Seal Islands?
Sentence (from "Ouvrage Simserhof"): Ouvrage Simserhof is a "gros ouvrage" of the Maginot Line, located near the community of Sierstal in the French "département" of Moselle.
Relevant evidence: No