Have you ever heard the saying “All roads lead to Rome” At one time, this was pretty much true. During the Roman Empire, lots of roads were built in order to move armies, send messages by courier (信使), and make trade easier.
The network of Roman roads was begun in 312 BC. It was demanded that the roads be built strong so that they would not fall down. Roman soldiers, supervised (监督) by engineers, laid down the roads in a special pattern of layers. There were all together 4 layers, which was made of different materials, such as sand, rocks, stones and so on.
Also, Roman roads were cambered (拱形). This means that they were built higher in the middle than on the edges, allowing rainwater to run off, which prevented flooding. We use the same technique in building roads today. The Romans also laid out roads over hills when necessary, setting them down in a zigzag (之字形的)pattern to make the road rise gradually.
All Roman roads had milestones (里程碑), placed every thousand paces (a Roman mile). The milestones told when the road was built, who was emperor at the time, the road’s destination, how far the traveler was from the destination, and how many miles had been traveled since the beginning of the road. This information was a great help to tra