Avatar: The Last Airbender2005

Joo Dee:
This is the lower ring.

Katara:
What's that wall for?

Joo Dee:
Oh, Ba Sing Se has many walls. There are the ones outside protecting us, and the one's inside that help maintain order. This is where our newest arrivals live, as well as our craftsman and artisans, people that work with their hands. It's so quaint and lively. [Cut to a shot of two shady men conversing in an alley. One of them is holding a large sword that glistens in the light. Both glare at the carriage as it passes] You do want to watch your step though.

Katara:
Why do they have all these poor people blocked off in one part of the city?

Aang:
This is why I never came here before. I always heard it was so different from the way the monks taught us to live.