Originally a mission station set up in 1554 by Jesuit priests on the banks of the Rio Tiete, the city of Sao Paulo is today an awesome megalopolis, the industrial and commercial powerhouse of Brazil. The city grew wealthy on coffee cultivation in the mid-19th century, thanks to the rich soil of the region, and the plantation owners took up residence in the bustling regional centre. Gradually the coffee barons diversified their interests and invested some of their wealth in local industry, resulting in a demand for labour and a resultant surge in immigrant population. Today 16-million proud 'Paulistanos' live in the congested, chaotic and cosmopolitan city centre and its sprawling surrounds. Lacking in natural attractions, the city’s leisure pursuits are mainly cultural, and there are some impressive public buildings to delight sight-seers.