AbstractIndustrial heritage is not just the industrial landscape, buildings, and material objects, but also the highly complex cultural heritage created by industrial society, with many unique features. The former industrial towns of East-Central European countries have little memory of their early capitalist industrial past, and their socialist legacy is mostly seen as an unwanted and unwelcome burden. Industrial heritage preservation in Hungary was also adversely affected by the ideology of de-industrialization in the late 1980s, and this was compounded by struggles over the politics of memory. Salgótarján, as the seat of Nógrád County, is a city with county rights that has one of the worst social and economic indicators in the country, with dozens of slums, many of them on former industrial sites. The number of sites suitable for greenfield investment in the valley town is low, while the proportion of under-utilized brownfields is high. The real turning point in the development of the settlement was the opening of the mines and the mining boom in the second half of the 19th century. The opening of the mines was soon followed by the construction of larger industrial plants: the steel mill, the hollow-glass and later flat-glass factory, and the ironworks (stove factory). Initially, skilled workers were recruited from abroad, which laid the foundations for a unique society, as much of the population had no ties to the settlement, or even to Hungary—only to the work and their employer. The industrial society of Salgótarján formed a well-defined local community with a sense of identity. The management of the companies and factories, the network of workers' welfare institutions, the managed leisure programs and facilities, and of course the built environment of the colonies played a major role in all this. Under state socialism, the factories continued to operate with an artificially inflated workforce, and after the political regime change in 1989, the privatized plants closed down with dramatic abruptness, leading to social trauma and high unemployment in the settlement. The preservation and presentation of industrial heritage is also important for the city's identity while the built environment is undergoing a radical transformation, which is why buildings that are deemed worthy of preservation should be given a new function as soon as possible so that they may remain an integral part of the settlement.