The building is a 19th-century red-brick block on Åboulevard by Emil Blichfeldt, who designed Tivoli — and it stands exactly on the line where scruffy Nørrebro becomes tidy Frederiksberg, so which city you are staying in depends on the direction you walk. Norrøn’s interiors go dark green on the ceilings and sage on the walls, in 91 rooms; the lobby is lit by custom metal fittings shaped like streetlamps.