Osaka-Kobe-Kyoto is the ninth largest city in the world by population - over 17 million people - 2,500 people per square km.  I'm soooo excited to move there.  When I lived in Maine, I wanted to move to Boston, the "big city."  When I first moved there, I remember feeling overwhelmed and lost, even like I didn't belong.  Now that I've been in Boston for about 5 years, I know it like my own house.