During this period the village of Mo i Rana was changed to an industrial city. People from all over the country moved to Mo i Rana in order to obtain work. The community needed homes for thousands of new residents. Construction of houses and residential blocks started immediately. It was also established electricity and water supply to the city. In 1930, the population was 1300 people, this increased to 7,000 in 1955. In 1978 The Iron Mill employed approximately 4,500 of the 25,000 town's inhabitants.