Green Goblin Mountains in the North Blue was both a mountain range as well as the symbol of an enormous sect. In the several tens of thousands of miles in the vicinity, there was probably no one who didn't know the prestige of its name.
Each and every person in the households of this region were determined to enter the Green Goblin Sect since they were children. However, very few people could enter this mountain sect considered as one of the top notch second tier sects in the Origin World.
According to the legends, the name came from the founder of the Green Goblin Sect who had once captured a green goblin beast some ten thousand years ago. Reportedly, this beast had already entered devil beast category
If it was still alive after ten thousand years, it would've certainly entered deity level.