Admit it--you've learned the dance and watched the clip; "Gangnam-style" is inescapable. (I even read that the Secretary General of the UN has called it 'a force for world peace.' Huh?) But what is "Gangnam" really like?

This district, south of the Han River in Seoul, was still rice-paddies until just a few decades ago. Perhaps no other neighborhood better sums up South Korea's explosive transformation from war-torn third-world ruins into high-tech pop-culture trendsetter. Nouveau-riche and ancient Buddhist culture rub shoulders here. Soak up K-pop style in Asia's largest underground shopping mall. Grab a coffee to go; marvel at the blocks of cosmetic-surgery offices.

After decades of function-over-form, artful architecture is beginning to take its place in the skyline, sharing the horizon with temple lanterns and forested hills. The historical heart of the Korean capital is north of the Han River, but its YouTube face is groomed here, in Gangnam....