The Residential Axis was intended to contain areas with intimate character and is considered the most important achievement of the plan; it was designed for housing and associated functions such as local commerce, schooling, recreations and churches, constituted of 96  limited to six stories buildings and 12 additional superblocks limited to three stories buildings; Costa's intention with superblocks was to have small self-contained and self-sufficient neighborhoods and uniform buildings with apartments of two or three different categories, where he envisioned the integration of upper and middle classes sharing the same residential area. But at that time he did not foresee the growing population in the city. The capacity limit in his plan later caused the formation of many favelas, poorer, more densely populated satellite cities around Brasilia, peopled by migrants from other place in the country. 