The city which is surrounded or enclosed by a wall is called walled city.There are some walled cities in world like Kowloon walled city,Lahore walled city.If there is no space between houses and markets and streets then this is walled city.It population fluctuates.There culture resembles to Hong Kong.Cities those are protected by the walls for there defense.some other cities are Dubrovink Croatia,York England,Israel, France. Toled,Spain. Xian,China etc.
*Its population fluctuates
Why did you mention Hong Kong?
I was not able to understand the reference to Hong Kong. Please write it again.