JUNIOR EDITION for Ages 6+
Cities: From Swamp to Superpower · Book 2

Cairo: The River That Fed an Empire

Why did one giant city grow on one spot of a very long river?

In this book, you will find out…

When you grow up, you could…

Who is in the story

AgastyaAgastyaWalks to the edge to see for himself.
CharlieCharlieAsks one good question — then lets Agastya find out.
WarrenWarrenTurns up late. Thinks about a hundred years from now.

Today’s mystery

Why did one giant city grow on one spot of a very long river?

Look for the clues. Try to guess the answer before Agastya does!

Chapter 1

The City That Stops

🔍 Where does the city end?
Cairo! Houses as far as Agastya could see.
Cairo! Houses as far as Agastya could see.
AgastyaWhere does it end? I'm going to find out.
Cars. Buses. Donkey carts. Everybody going somewhere at once.
Cars. Buses. Donkey carts. Everybody going somewhere at once.
He walked and walked. Tomatoes, onions, a busy Tuesday.
He walked and walked. Tomatoes, onions, a busy Tuesday.
Then the street just stopped. One last house. Then sand.
Then the street just stopped. One last house. Then sand.
Behind it, nothing. No houses at all. Desert, for days and days.
Behind it, nothing. No houses at all. Desert, for days and days.
Agastya looked down. A little ditch. Green on one side. Grey on the other.
Agastya looked down. A little ditch. Green on one side. Grey on the other.
Clover, a buffalo, palm trees. And the desert, right behind them.
Clover, a buffalo, palm trees. And the desert, right behind them.
He sat right on the line. He had a guess.
He sat right on the line. He had a guess.
AgastyaNobody drew this line. The water did!
He followed the green back. It led to a water gate. His guess was right.
He followed the green back. It led to a water gate. His guess was right.
Agastya’s notebook
The city stops where the water stops.
From space, Egypt is one green ribbon in the brown. But why is the city right HERE?
From space, Egypt is one green ribbon in the brown. But why is the city right HERE?
Chapter 2

One River, One City

🔍 Why did the city grow on this spot?
Charlie asked just one thing.
Charlie asked just one thing.
CharlieThe river is long. Why this bend?
Agastya was quick.
Agastya was quick.
AgastyaBecause the river is here. Cities need water.
So he took a boat south to check. Same river. Just a small town.
So he took a boat south to check. Same river. Just a small town.
And a village. And another. Same water, but no giant city.
And a village. And another. Same water, but no giant city.
Agastya crossed out his answer. Then he spotted something. Most boats went north.
Agastya crossed out his answer. Then he spotted something. Most boats went north.
He followed them. Past the city, the river split in two!
He followed them. Past the city, the river split in two!
Behind the split, farms spread out as far as he could see.
Behind the split, farms spread out as far as he could see.
He drew it twice. Then he got it.
He drew it twice. Then he got it.
AgastyaIt's like a funnel. And Cairo is in the neck!
🔎 Clue found!
Cairo sits where the river splits. Everything must pass here.
One narrow valley. One wide fan. But how do boats even get up the river?
One narrow valley. One wide fan. But how do boats even get up the river?
Chapter 3

Up and Down for Free

🔍 How do boats go both ways with no engine?
Agastya saw two boats. One had its sail up. One had its sail down.
Agastya saw two boats. One had its sail up. One had its sail down.
The first sailed UP the river, against the water.
The first sailed UP the river, against the water.
The second just floated DOWN. Nobody rowed at all.
The second just floated DOWN. Nobody rowed at all.
Agastya decided to test it himself.
Agastya decided to test it himself.
AgastyaWhich way is the wind? Which way is the water?
He looked up. Flags and washing all leaned south.
He looked up. Flags and washing all leaned south.
He looked down. A bit of weed floated north.
He looked down. A bit of weed floated north.
Agastya worked it out by himself.
Agastya worked it out by himself.
AgastyaWind pushes you up. Water carries you down!
Agastya’s notebook
Sail up. Float down. A free road both ways.
Grain came down the river. Stone went up. For thousands of years.
Grain came down the river. Stone went up. For thousands of years.
A road made of water. But where did all the food come from?
A road made of water. But where did all the food come from?
Chapter 4

The Flood Nobody Feared

🔍 Where does a flood come from when it never rains?
In the old days, every summer, the river flooded the whole land.
In the old days, every summer, the river flooded the whole land.
But it hardly ever rains in Cairo. Agastya was puzzled.
But it hardly ever rains in Cairo. Agastya was puzzled.
AgastyaThen where does the extra water come from?
Far, far away, rain falls on mountains for months.
Far, far away, rain falls on mountains for months.
The rain rushes down the river. It carries brown mud with it.
The rain rushes down the river. It carries brown mud with it.
When the flood went away, new mud was left on the fields.
When the flood went away, new mud was left on the fields.
Agastya picked some up. Soft and rich.
Agastya picked some up. Soft and rich.
AgastyaThe flood brings new soil every year!
At the river bank, he saw stripes. Each stripe was an old flood!
At the river bank, he saw stripes. Each stripe was an old flood!
🔎 Clue found!
The flood brought water AND new soil, free, every year.
So farms here grew lots and lots of food. Then Agastya found a strange building.
So farms here grew lots and lots of food. Then Agastya found a strange building.
Chapter 5

The Stairs in the River

🔍 What are these stairs for?
Stone stairs went down into water. A stone post stood in the middle.
Stone stairs went down into water. A stone post stood in the middle.
The post had lines on it, from top to bottom.
The post had lines on it, from top to bottom.
Agastya looked closely.
Agastya looked closely.
AgastyaIt's a ruler! They measured the river.
He was right. A tunnel let the river in, so people could read it.
He was right. A tunnel let the river in, so people could read it.
Charlie asked only one thing.
Charlie asked only one thing.
CharlieWho wants to know first?
Every day, a man shouted the number through the streets.
Every day, a man shouted the number through the streets.
High river, big harvest. The rulers knew how much grain to ask for!
High river, big harvest. The rulers knew how much grain to ask for!
Agastya wrote it down fast.
Agastya wrote it down fast.
AgastyaThey knew the harvest before it grew!
Counters, offices, rulers. They all came to sit here. But what did they do with the grain?
Counters, offices, rulers. They all came to sit here. But what did they do with the grain?
Chapter 6

Follow the Grain

🔍 Why so many grain stores?
Agastya found rows and rows of old grain stores.
Agastya found rows and rows of old grain stores.
He guessed.
He guessed.
AgastyaTo keep food for a bad year?
So he followed the grain. Men carried the sacks onto boats.
So he followed the grain. Men carried the sacks onto boats.
Lots of boats! All floating down the river together.
Lots of boats! All floating down the river together.
At the sea, the grain went onto big ships.
At the sea, the grain went onto big ships.
It sailed all the way to a huge city across the sea.
It sailed all the way to a huge city across the sea.
So the grain was for selling!
So the grain was for selling!
AgastyaEveryone wanted Egypt's food.
🔎 Clue found!
Egypt grew food for other countries too.
On a map, Agastya saw old cities, all on the very same spot. Why?
On a map, Agastya saw old cities, all on the very same spot. Why?
Chapter 7

Five Good Things in One Place

🔍 Why did everyone build right here?
Very old kings built here.
Very old kings built here.
Later rulers built here too. Then came Cairo.
Later rulers built here too. Then came Cairo.
He put five dots on his map. They almost touched!
He put five dots on his map. They almost touched!
AgastyaThey all picked the same spot.
Charlie made him say it carefully.
Charlie made him say it carefully.
CharlieNot just "the river". Name each thing.
One: an island in the river.
One: an island in the river.
Two: a crossing that every traveller uses.
Two: a crossing that every traveller uses.
Three: a hill, in a land that is all flat.
Three: a hill, in a land that is all flat.
Four: building stone, close by.
Four: building stone, close by.
Five: a good start for a canal to the other sea.
Five: a good start for a canal to the other sea.
Agastya read his list again.
Agastya read his list again.
AgastyaOther places have one. Cairo has all five!
Agastya’s notebook
Island. Crossing. Hill. Stone. Canal. All in one spot.
But there is a better harbour, by the sea. Why isn't the big city there?
But there is a better harbour, by the sea. Why isn't the big city there?
Chapter 8

The Day of No Flood

🔍 So — why here?
Agastya went to see the sea port. Ships, cranes, boxes.
Agastya went to see the sea port. Ships, cranes, boxes.
But it was far from the river. They even had to dig a canal.
But it was far from the river. They even had to dig a canal.
Agastya saw it himself.
Agastya saw it himself.
AgastyaThe port faces out. Cairo sits in the middle.
Back in Cairo, it was flood time. But the river was calm and low.
Back in Cairo, it was flood time. But the river was calm and low.
Far up the river, a giant dam now holds the flood back.
Far up the river, a giant dam now holds the flood back.
Now water comes all year. Farmers grow three crops, not one.
Now water comes all year. Farmers grow three crops, not one.
Charlie asked one last time.
Charlie asked one last time.
CharlieSo. Why here?
Agastya answered by himself.
Agastya answered by himself.
AgastyaWater and mud. Boats both ways. And the neck where it splits.
By the river, Warren was waiting.
By the river, Warren was waiting.
WarrenWill the river still feed Cairo in 100 years?
Agastya thought of the dam and the mud.
Agastya thought of the dam and the mud.
AgastyaOnly if people share it and look after it.
On the way home, he looked out of the window.
On the way home, he looked out of the window.
AgastyaEvery city is somewhere on purpose.

All the clues

  1. Cairo sits where the river splits. Everything must pass here.
  2. The flood brought water AND new soil, free, every year.
  3. Egypt grew food for other countries too.

So… Why did one giant city grow on one spot of a very long river?

The river gave water and new mud every year. Boats could sail up and float down. And at Cairo, the river splits — so everything has to pass this one spot.

OmahaIndia Junior · a simpler version of Book 1 for readers aged 6-8