Town and city walls are some of the oldest things ever built. Walls began to appear around places such as Jericho in the Middle East, about 10,000 years ago. That was a small town wall, but it was 4m tall and an important model for every other town and city. The world's first city, Ur, built by the Sumerians in Mesopotamia (now Iraq) had a long wall. The Greeks and Romans built walls around all of their cities at home and in their colonies. The Romans, for example, built a great wall around London, and guarded it with a fort in one corner. The Iron Age Hill forts of Europe were huge earthen walls surrounded by ditches and designed to protect a whole clan in times of attack. By medieval times almost all towns and cities in the world had walls.
Walls were important for many reasons. They were useful for keeping out wild animals at night. They were useful at stopping raids either by renegade bands of warriors or armies of attacking troops. They were also useful for making sure people paid taxes on goods going in and out. In effect they were customs stations such as we might find at ports today.
Walls were needed because a town or city is a prize for anyone attacking it. Not only would there be wealthy people who could be ransomed, but there would be great stocks of merchants' goods, and people concentrated in one place who could be taken as slaves.
Walls were strong. They were defended just like a castle, and mostly had crenellations and towers to help in the defence. The weakest place was the gate, and this was usually strengthened by a double tower.
The picture shows York in NE England, one of the best-protected cities in Europe in the Middle Ages.
City walls kept people safe and were protected by townsfolk who either provided workers to help to man the defences, or paid for others to defend them. Cities walls were rarely destroyed, so attackers had to set up a siege, and they often decided it was not worth it. But the wall is very poor at defending against cannon and other explosive devices and so when cannon were invented, most walls were pulled down. Fortunately some still survive. In any case, the wall hemmed people in, making it hard to expand, and as towns and cities grew, they became more and more dense, with buildings rising higher and higher. In cities like Strasbourg near the Rhine in France, the houses reached skyscraper heights of eight or more stories.
The video shows a small Italian fortified town called Glurns that is more or less as it was in medieval times. It even has the gates and a complete wall. You can imagine all European cities looked like this.
