Lin Xun had mastered the secret technique for constructing the Dragon Watching Platform. However, this type of teleportation structure had certain requirements for its location; it couldn't be built just anywhere. The Dragon Watching Platform needed to be built atop a "Dragon Vein."
According to the Vermilion Geography Records, what used to be called "Dragon Vein" had been renamed to "Long Vein", referring to a mountain range system that contains immense and unbroken earth energy.
Because its contour winds and undulates like a dragon, lively and flexible, hence the mountains are metaphorically called "dragon," and "vein" indicates the mountains' continuity and vitality.
Kunlun was originally a true Dragon Vein, and could even be considered the starting point of all Dragon Veins in the world. However, Kunlun was designated as part of the Small Thousand World due to Yama God's power, severing its connection with the Great Thousand World.