Question: Holger Sinding-Larsen was most associated with his work at a fortressed used as what?
Sentence (from "Akershus Fortress"): Akershus Fortress (Norwegian: "Akershus Festning" ) or Akershus Castle (Norwegian: "Akershus slott" ) is a medieval castle that was built to protect Oslo, the capital of Norway.
Relevant evidence: No