Through the first half of the 20th century, Seoul seemed destined to remain in the shadow of the region's neighboring mega-cities Tokyo and Beijing. Since the late-80s, however, the South Korean capital has thrown its hat into the ring and assertively managed to attract vast amounts of culture and commerce.
For nearly two thousand years, China's imperial rulers built and expanded the Great Wall - the world's largest work of military architecture - for just one purpose: to protect the empire from an invasion by foreign barbarians and their culture. This mindset continues to this day - as evidenced by the construction of China's Great Firewall - so the wall seems like an unlikely site to invite a series of foreign architects to join their Chinese counterparts in creating a cluster of experimental works aimed at attracting visitors from all over the world.
With its 32 million inhabitants, Tokyo is by far the biggest metropolis of the developed world. However, it is not necessarily its size as much as its relentless pace and extraordinary capability to adapt to new conditions that makes the city so unique. Like Kenzo Tange and his fellow Metabolists famously noted, Tokyo has the appearance of a sophisticated organism with a highly developed metabolism, constantly modifying its own urban fabric.