These are 5 position alpha-numeric codes comprising the d series. All other level II codes and descriptors are approved and maintained jointly by the alpha-numeric editorial panel (consisting of CMS, the Health Insurance Association of America, and the Blue Cross and Blue Shield Association).
Alaska: Although Alaska enjoys a high volume of aurora activity, its cruises are not often mentioned as northern lights cruises. During the Alaska cruise season, it's rarely dark enough for the lights to be visible.
Northern Lights in Iceland. Iceland is a scarcely populated arctic island, with many wild, unpolluted places to see the Northern lights. Even though the lights of Reykjavik can't hide them, then they may be even brighter outside the city limits.