Okay kiddo, a long time ago, before cars and buses and trains, people used to travel on foot or on animals like horses, donkeys or camels. And they needed clear and safe paths to travel from one place to another.
A king's highway was a very special road built and maintained by a king or his government to connect different parts of his kingdom. These were special because they were built to last a long time and were wider and more straight than other paths.
The king's highways were also important because they allowed traders and messengers to easily travel between different cities and towns without getting lost or attacked by robbers. This helped to grow the economy and trade among different regions.
Over time, the king's highways became more and more sophisticated, with better paved roads, bridges, and tunnels. Today, many of these ancient highways are still used and are considered important historical sites.
So, the king's highway was like a special road built by a king to connect different parts of his kingdom and make trade and communication easier!