20. Aligarh, India
> Population density: 54,368 people per square mile
> Population: 2.1 million
> Built-up land area in city: 38 square miles
19. Ahmadabad, India
> Population density: 55,518 people per square mile
> Population: 7.7 million
> Built-up land area in city: 139 square miles
18. Patna, India
> Population density: 55,983 people per square mile
> Population: 3.2 million
> Built-up land area in city: 58 square miles
17. Mumbai, India
> Population density: 57,033 people per square mile
> Population: 22.2 million
> Built-up land area in city: 389 square miles
16. Al-Mahallah, Egypt
> Population density: 57,857 people per square mile
> Population: 810,000
> Built-up land area in city: 14 square miles