The world’s first Northern Lights observatory is the focus of this account about everyday life and epoch-making pioneering of geophysical research on Haldde Mountain in Finnmark, Norway. Inside four walls in extreme weather conditions at 9000 metres above sea level, the residents formed a class-divided mini-society with researchers, assistants, wives and maids.This book provides an insight into eventful years of the last century. Children are born, photographs and measurements of the Northern Lights are taken, the research develops, and important people die. The work conducted on Haldde Mountain resulted in a geophysical institute and weather forecasting services for Northern Norway and was the basis for the foundation of Norway’s most northern university. The book builds on private letters, memoirs and archive material about daily life and research.