About how these cities no one has ever heard of would be the big city in other parts of the country.
China is like that a hundredfold. They have so many cities that would be metropolises (metropoli?) in other parts of the world, but are almost considered villages there.
For example, my nephew's wife is from a tiny village in the middle of China, with the minuscule population of about 100,000.
Looking at the list, I count 90 cities with over a million in population, 120 if you include the whole metro area.