Okay kiddo, imagine you have a really important job, like a king or a queen, and you need to travel to different places. You could take a car or even a plane, but sometimes it's nicer to take a special train.
In North Korea, the leaders, or the people in charge, also like to take special trains when they travel. These trains are called "Great Leader's trains" and they are very fancy and big. They have lots of different rooms and things inside, like bedrooms, kitchens, and even a conference room.
When the leader travels on these trains, they have everything they need with them, like food, clothes, and all their important papers. They can also use the train as an office and make important decisions while they are traveling.
The reason these trains are so important is because North Korea doesn't have a lot of good roads or airports, so it can be hard to get around. The trains are a good way for the leader to see different parts of the country and meet different people.
But there's something else important about these trains, kiddo. Sometimes people in other countries want to know where the North Korean leader is traveling to, because it could be a sign of what they're planning to do next. So, the North Korean leaders try to keep their travel plans a secret, and that's why they use these special trains. It's like a secret hideout on wheels!