Being different than ordinary people, when Zhang Tie read a map, he kept visualizing the images and data about terrains on the plane into a huge three-dimensional sand table. In this way, he could bear everything on the map in mind for the rest of his life.
Whenever Zhang Tie wanted to use it, he could deepen into each detail on the map. Additionally, when in flight, Zhang Tie could match the coordinate on the map at any time. Therefore, he would not get lost no matter how long he had flown. Furthermore, Zhang Tie could match all the coordinates in mind and draw out the most precise map.
After reading it, Zhang Tie realized the large size of Motian Realm. Those regions marked on the map were much larger than the world that he came from.
However, the size of Motian Realm was relative.