All the people in the world standing shoulder to shoulder would take up only 500 square miles (1300 square kilometers). That's just slightly bigger than the size of the city of Los Angeles.
Almost half the population of Hong Kong lives in an apartment that is on the 15th floor or higher.
Australia is the smallest, and also the lowest continent on Earth. About 75% of it's land is unable to produce any kind of crop.
A city the size of New York consumes 1 billion U.S. gallons of water per day; enough to fill 1,480 Olympic sized swimming pools.