Barra da Tijuca, Brazil

With a population of just 39,403, Barra da Tijuca is touted as one of Brazil's most developed neighborhoods, but the reality is more complex. While the area boasts a high human development index and lavish condos, it's also plagued by a car-centric culture and bureaucratic headaches that make daily life a slog. The rapid population growth - from under 100,000 in 1991 to over 300,000 today - has strained infrastructure, and the neighborhood's separation from central Rio by difficult-to-cross mountain ranges only compounds the challenges. Barra da Tijuca may offer an exclusive, manicured lifestyle for the upper classes, but it's not for those seeking an easy, integrated urban experience.