The Maranho arrived at the decade of 1960 with a very restricted industrialization, counting only on some plants of wiring and weaving, having as raw material the cotton. It enters the years of 1960 and 1970 its economy gains impulse through investments in the sectors of farming and the vegetal and mineral extrativismo, stimulated for the tax incentives of the Supervision of the development of the Amaznia (SUDAM) and the supervision of northeast development (SUDENE), with great projects of creation of cattle, plantation of soy and rice and iron ore extration, as the project great Carajs (PGC), bringing wealth, but also increasing agrarian concentration, thus causing, enormous ambient problems. The implantation of the siderurgical industries in the city of Aailndia is on to the program Great Carajs, one of the biggest programs of economic development of Brazil, that has as objective the mineral exploration of the known region as Carajs, geographically located in the South of the state of Par, with the installation of the industries of the iron-gusa in the city, end of the decade of eighty, induced one for a favorable endowment of natural resources, including if the ore of iron, main insumo in the production of iron-gusa, proceeding from the province mineral of Carajs through the just-constructed railroad Carajs. Gusa, as it is called, is the intermediate form for which it practically passes all the iron used in the production of the steel, gotten from the ore fusing of iron in high ovens, where mineral coal (coke) or vegetable is used as reducing agents and power plants. The guseiro polar region of Aailndia works to take care of two markets: the intern (gusa importation), located in the south of the country, and the external one (gusa exportation), distributed between Europe, Asia and United States. With the conditions you propitiate for the act of receiving of the industries of the iron-gusa, the city was visited by innumerable entrepreneurs, owners of siderurgical of the independent type, proceeding from the state of Minas Gerais, one of the states where first if they had installed the iron-gusa industries in the country..