During the second half of the 20th century, the area outside the port of Gijón was established into three main areas: the coast strip between the city and El Musel where the facilities and shops dealing in the construction and repair of ships proliferated, the iron and steel area in which the former UNINSA is located with its modern Veriña factory, first reconverted into ENSIDESA and finally into ACERALIA, and the Aboño valley (Carreño), where companies of the size and importance of Tudela Veguín and Hidroeléctrica del Cantábrico were established.
As the industrial activity developed, the city and its countryside outskirts were transformed both socially and in terms of urban planning with thousands of families settling in what were to become heavily populated neighbourhoods. The business initiative with the promotion of housing in El Natahoyo and La Calzada helped this flourishing that began before the Spanish Civil War, particularly through companies such as La Asturiana, Gijón Fabril and La Algodonera.
From the 1940s, business property promotion increased even further based on both the “paternalism” encourage by the regime of the time that sought to establish employees close to their workplace and on the scarcity or demand of the employees themselves.
Hence, large populations arose that were spread around the different districts of Gijón, sharing what had until then been peripheral areas of settlement. As a result, these areas where often undeveloped and lacked services, particularly around its traditional or newly formed industries such as La Calzada or Pumarín, respectively.
This was the case of the UNINSA factory that was set up in the Veriña valley and led to a flood of new jobs and employees from the old plants in Mieres and Langreo. In order to deal with this mass of displaced people, one of the clauses of the consensus agreement signed by the company in 1966 forced it to build 2000 homes for middle and lower category employees. The establishing of the new iron and steel complex and the development and expansion of the port area in Gijón was to strengthen the citys demographic boom of the sixties and seventies to give a rise in the number on registered inhabitants from over 121,000 in 1961 to 237,200 in 1975.
As a result of the economic recovery of the sixties, official initiatives to meet the deficit in terms of accessible housing led to their first and most significant offering in Pumarín with the so-called Estate of the 1500′, through a 1953 decree that charged the National Housing Institute with their construction on land provided by the municipality.