Reverse Mountain is one of the entrances to the Grand Line. It is located in the Red Line and it is located in the opposite side of the world from Mary Geoise.
Reverse Mountain is a tall mountain, the point where the four Blues meet and is one of the entrances to the Grand Line. This place is unique in the sense that the rivers from the Blues flow up the mountain and meet at the top, they then all flow down to the Grand Line. Reverse Mountain is known to be a ‘Winter Island’.
The mountains have five rivers in which four of them are ascending from each of the world’s four Blue Seas and one is descending into the Grand Line. The entrance of the river is in ten square acres that are decorated with tribal patterns and depictions of sea creatures.
The people who live on Reverse Mountain are:
Laboon is the whale that the Straw Hats crew met on Reverse Mountain. He is from the West Blue and is known as ‘Big Friendly’ and is quite friendly.
Crocus is a doctor and the caretaker of Laboon and he also oversees the Twin Cape Lighthouse. He was also the doctor of Gol D. Roger’s crew.
The tribal patterns on Reverse Mountain gates are in common with the tribal patterns found in the ruins of Shandora.
We get to see Reverse Mountain during the Reverse Mountain Arc that takes place in Twin Cape.
Reverse Mountain is called a ‘Winter Island’ because it is much colder than the surrounding sea on the Blues but not in the Grand Line.