Duque de Caxias, Brazil

With a population of 667,821, Duque de Caxias is no charming backwater. This industrial suburb of Rio de Janeiro has undergone a bumpy transformation, emerging as a bustling economic hub - but not without its persistent headaches. The city's strategic location near major highways and airports has attracted big businesses, yet the relentless deforestation and poor sanitation of the past still linger as a burden. Bureaucracy is a known thorn, with emancipation efforts facing harsh government crackdowns in the 1940s. While Duque de Caxias offers job opportunities and a lower cost of living compared to the glitz of Rio, its gritty urban sprawl and uneven development make it a better fit for pragmatic, thick-skinned types rather than those seeking an easy expat lifestyle.