Ur Mesopotamia 2000 BCE Rome 200 Beijing 1300 Brasília Brazil 1956 1960
One Mapping It Out Baghdad 762 Only 9,000 years ago give or take cities didn’t exist Today about four billion people about half the world’s population live in cities This number could rise to seven billion by 2050 What is a city It turns out there’s not just one definition that everyone agrees on Some countries define cities based on the number of residents others by the type of work done by the people living there City populations range from 1,500 to 50,000 to millions of people But what makes a city a good place for people to live Is it its shape or size The number of services it has like libraries hospitals or shops Is it having parks where you can enjoy nature and see your friends Or is it having a low level of crime pollution and noise Cities have changed a lot over time Let’s take a look at how they got started and what they might look like in the future 5
Babylon in ancient Mesopotamia was surrounded by walls that were 30 to 40 feet 9 to 12 meters high and wide enough to accommodate chariot races LOCATION LOCATION LOCATION Permanent settlements began to take root when people discovered they could stay in one place and grow grains such as barley and emmer an ancient kind of wheat instead of moving around to find food the way their ancestors had The first cities showed up around 7500 BCE in Mesopotamia 3300 BCE in the Indus Valley of present-day Pakistan and India and 3100 BCE in Egypt If you had a lake or river for water plus some invader stopping geography such as an island or a hilltop with good views of approaching enemies you had yourself a good location for a city If you were a ruler you’d likely build a temple or palace right in the center of your city Let’s Trade With grain safely stored behind temple walls and farmers harvesting more food than they could eat some people were freed up to do other jobs like weave cloth or make baskets A farmer could now trade grain for a pottery jar at the local market Merchants traded goods with nearby cities and towns were established along trade routes such as the Silk Road One of the World’s First Megacities Around 2,000 years ago one million people lived in ancient Rome After developing their own type of concrete in the first century Romans built monuments that still stand today The Colosseum was an amphitheater that hosted gladiator battles and wild-animal hunts Wealthy Romans lived well but most people lived in crowded buildings called insulae which were apartment buildings so poorly built that they sometimes collapsed Rome faced constant threats In 410 CE invaders held the city hostage for three days until they were given 2 tons 1.8 metric tons of gold 13 tons 11.8 metric tons of silver 4,000 silk tunics 3,000 fleeces and 3,000 pounds 1,361 kilograms of black pepper Dhaka Bangladesh 21 million 2020 Mexico City 18 million 2000 Population of Megacities Through Time New York City 12 million 1950 London England 6 million 1895 Alexandria Egypt 1 million 100
If You Lived in Ur Mesopotamia Around 2000 BCE Ur was a busy city of 65,000 people next to the Euphrates River in today’s Iraq Many people farmed but your parents might also have woven cloth or made pottery You lived in a mud-brick house with a central courtyard on a narrow winding street that provided shade from the fierce Mesopotamian sun After practicing letter-writing on clay you played board games carved on bricks or raced clay model boats
