The Great Wall of China is made of stones, bricks and wood. It is 8851 km long. It can take months to walk the Great Wall of China because of how long it is and it is so collosal that you can see it from space but you have to use a telescope then you can see it all the from above Earth it’s self.
The Great Wall of China has had no upgrades since 1644 also one quarter of the wall has disappeared.
The most visited area of the wall is very popular with 63,000,000 visitors there.