- Cities have been critical in human development for almost 10,000 years.
- We looked at thousands of years' worth of data to determine the 16 greatest cities in human history.
- Each entry on the list was a center of commerce, technology, and innovation, from ancient Jericho to modern-day Tokyo.
Cities have played a crucial role in human development for more than 9,000 years.
From Jericho, the oldest known city in the world, to Tokyo, the largest city today, cities have served as centers for commerce, technology, education, and culture.
And cities are continuing to grow to new heights. In 1960, there were two rural dwellers for every city dweller in the world. But as the biggest wave of urbanization in human history continues, more than half of the world's population now lives in urban centers.
We looked at data spanning thousands of years to compile this list of the greatest cities of all time. Although determining the exact population of ancient cities is no easy task, we used research from historians Tertius Chandler and Gerald Fox in their book "3,000 Years of Urban Growth" and political scientist George Modelski's 2003 book "World Cities, -3,000 to 2,000."
The numbers were drawn from the size of a city's military in peacetime and in war, household data, agricultural commerce, church records, fortification sizes, food distribution, loss of life in a disaster, and city comparisons.
Read on to see the 16 greatest cities in human history:
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Jericho: The world's largest city in 7000 BC
Population: 2,000
Present-day population: 14,674
Jericho may be the oldest continually occupied spot in the world, with settlements dating to 9,000 BC.
The city, nestled between the Dead Sea and Mt. Nebo, had natural irrigation from the the Jordan River and the best known oasis in the region.
The springs allowed residents to grow the highly lucrative opobalsamum plant, which produced the most expensive oil in the ancient world.
At the dawn of the earth's prehistory, the residents of Jericho enjoyed architecture that included a religious shrine and painted skulls that made up the first ever attempt at portraiture.
Uruk: The world's largest city in 3500 BC
Population: 4,000 people
Present-day status: Ruins
Some believe Uruk to be the biblical city of Erech; the second city built by King Nimrod in the Book of Genesis.
The domestication of grain and its close proximity to the Euphrates River allowed Uruk's harvest to swell, leading to trade, advancements in writing, and specialized crafts.
Excavation in the region is difficult because older buildings were recycled into newer buildings throughout the ages.
Located between the Tigris and the Euphrates, Uruk went on to become part of Mesopotamia, meaning"land between rivers."
Mari: The world's largest city in 2400 BC
Population: 50,000
Present-day status: Ruins
Mari was the robust trade capital of Mesopotamia. Located in present-day Syria, the city was central in moving stone, timber, agricultural goods and pottery throughout the region.
Mari's government swelled along with its economy in the second century BC, and in the 1930's a French archaeologist discovered 25,000 tablets written in an extinct language called Akkadian.
Most were municipal documents, economic reports and census rolls — a third were personal letters.
The find changed our understanding of the ancient Near East.
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