One Piece is currently in the Elbaf arc, and fans are eagerly waiting for Oda to reveal some of the biggest secrets of the world.
The World of One Piece is Known as the Blue Planet
The world of One Piece is incredibly vast, yet there is still very little information that fans know about it. The One Piece world features a variety of interesting countries, with many islands scattered throughout and a significant portion covered by the Grand Line. There is a massive continent that runs through the world, known as the Red Line. Perpendicular to the Red Line is another line of ocean called the Calm Belt, where winds do not blow. The Grand Line itself is divided into two parts by the Red Line: the first half is referred to as Paradise, while the second half is called the New World. Together, the Red Line and the Grand Line divide the One Piece world into four seas: North Blue, East Blue, South Blue, and West Blue. This is the world as fans know it.
In the ongoing Egghead arc, fans are learning much more about the current state of the One Piece world. 900 years ago, the One Piece world was not covered by the Grand Line as it is today. In fact, the great war has been said to have occurred at a depth of 200 meters below the surface. In other words, the One Piece world currently exists beneath the Grand Line.
Recently, Oda has also hinted at the name of the planet once again. He has officially revealed the name of this planet to fans.
Question: Odacchi, hello! In chapter 987, the bridge that Roger and Oden saw is called Tequila Wolf? Or Bourbon Wolf? And what is the name of the planet where Luffy and the others are sailing?
Oda: What? Are you focusing on the right thing? The planet is called “Blue Planet.” And the bridge that Oden saw… cannot be Tequila Wolf! How would I know the answer? I won’t say it’s Bourbon Wolf, but it definitely isn’t Tequila Wolf. That is my answer! We discovered four bridges in chapter 1125, so you can’t know the answer in chapter 967. But looking back, why did I think that? Amazing.
The Country of Elbaf Has Existed for Over 3000 Years in One Piece
Fans know very little about the historical background of the One Piece world. However, Elbaf has provided readers with detailed information once again. Specifically, in chapter 1144, Oda revealed that the One Piece world has countries that have existed for about 3000 years, if not longer. Up to now, fans know very little about the distant past, and most assume that this world has been present for at least 900 years.

So far, Oda has confirmed that 900 years ago, the world did not exist as the initial world, but it has actually been a world of post-destruction. The original world of One Piece had existed for a very long time before that.
Additionally, Lilith, one of the Vegapunks, revealed in One Piece chapter 1144 that the scientific base they encountered in Elbaf is at least 3000 years old. In other words, Elbaf has existed since the time of the first world at least 3000 years ago. This also makes it one of the oldest countries known in the One Piece world.
There are two other very old countries that fans know of in One Piece. These two countries are Arabasta, which was established about 4000 years ago, and Ohara, where the tree of knowledge was planted about 5000 years ago. However, because Elbaf is directly related to Nika, it is likely to have existed longer than those two countries, especially when considering the age of the Ancient One, particularly the Ancient One that has a direct connection.
Although this may surprise many, it is not less than that. After all, Vegapunk revealed in the Egghead arc that the stories about Nika, the Sun God, originated from Elbaf. In fact, Joy Boy, who possesses the rubber powers of Nika, has been directly compared to the legendary Sun God of Elbaf thousands of years ago. In other words, Nika is an Ancient One from Elbaf and has existed for over 3000 years in the world of One Piece.

Based on all the information that fans have received to date, it is clear that the first world existed around 3000 years ago, which means that anything mentioned in the Harley documents about the first world must have occurred during this timeframe.
The emergence of Nika means that the peaceful era is currently being destroyed, and this is related to the Earth God and Serpent of Hellfire working together to destroy the world. There is a possibility that Nika had died, but the entire world still exists. Humanity no longer exists in many places, and what remains is only the remnants of the world. Elbaf clearly managed to survive despite all the circumstances, but a large part of its population may have been erased.