See Urbanization Happen

Sustainability
Archaeology
Behavior

Visualizations are very helpful in thinking about things that occur over time.  The History of Urbanization: 3700 BC - 2000 AD from Metrocosm, does just that.

Creator Max Galka notes that By 2030, 75 percent of the world's population is expected to be living in cities. Today about 54 percent of us do. In 1960, only 34 percent of the world lived in cities.

Galka tells us how the data before then were obtained.  In addition, Galka plots these data in Mapbox which allows further exploration. 
 Neat!