Poneglyph

Poneglyphs are mysterious stone blocks with history inscribed on them in the form of strange letters. They are scattered among the islands of the world, and it is said the only person left in the world who can read them is Nico Robin.

Appearance and Types
Poneglyphs are massive blocks made of an indestructible type of stone. They have text carved on them, written in an ancient language.

There are about 30 poneglyphs throughout the world, and they can be divided into three types: Historical, Instructional and Road Poneglyphs. "Historical Poneglyphs" reveal pieces of ancient history as well as messages written by ancient people. There are a total of nine Historical Poneglyphs. "Instructional Poneglyphs" contain instructions and/or clues about the locations of Historical Poneglyphs and Ancient Weapons, which are of a total of 17. Both Historical and Instructional Poneglyphs are of a dark blue color. The third and last type of poneglyph is the "Road Poneglyph" (ロード歴史の本文（ポーネグリフ）), which gives away a location that, when pieced together with the locations given by the other Road Poneglyphs, allows one to find the path to Raftel. Those poneglyphs are of a deep red color and there are only a total of four of them.

Aside from the poneglyphs, there are also other stones that, while not being poneglyphs themselves, contain the same ancient language found on the poneglyphs, such as certain walls in the ruins of the ancient city of Shandora.

Overview
According to Tamago, there are about thirty poneglyphs in the world. The blocks are indestructible; it has been stated that not even explosives could leave a scratch on these stones.

Each one tells a piece of history long forgotten. This history includes mentions of (at least) three weapons of mass destruction: Pluton, Poseidon and Uranus. In the eyes of the World Government, they are dangerous artifacts, and despite declaring the stones dangerous because of the weapons, the reality is that the ideals of the fallen Kingdom written on some of the stones are far more dangerous than any of the weapons. The Road Poneglyphs are sought by several organizations interested in the artifacts found in Raftel, to the point that two of the Yonko, Charlotte Linlin and Kaido, have each claimed possession of a Road Poneglyph.

Keep thy motives in heart, with closed mouth. We are those who will weave history with the ringing of the great belfry.

The stones are left in the care of the descendants of the ancients, as seen in both Alabasta and Shandora. The Shandorian Poneglyph was a fiercely guarded treasure of the Shandorian people and they felt a deep visceral connection to it (namely the bell built around it), that was passed down up to the present era where the descendants of those who fought and died to protect it still put their lives on the line to reclaim it - along with their homeland - even though they had forgotten about the existence of the poneglyph itself. They still cherish what it represents a great deal, and the shaman of their people openly wept upon hearing they had fulfilled the wishes of their ancestors by passing its information on to Nico Robin, and freeing them from their centuries long burden.

Unlike its Shandorian counterpart that was guarded by its people to protect the information in contained, it is clear that the hidden nature of the Alabasta poneglyph was to conceal its existence from the people, and not protect it, as Alabasta is an affiliate of the World Government united against the creators of the poneglyph. This is also inferred by Nico Robin in her conversation with the King of Alabasta, Cobra, when she scoffs at and rebukes his statement about a hereditary charge of the monarchy to 'protect' the stone, although he himself is truthfully unaware of the deeper reasons or motives of its concealment decided long before his time.

However, only when the stone has been read by someone willing to take the read passage to the ends of the Earth, are those guarding them allowed to be free of the burden. In order to prevent these historical facts from being lost forever, they had carved them into these poneglyphs, which are indestructible. Regardless, to reach and decipher the Rio Poneglyph is the ultimate goal of Nico Robin, and it has brought herself much unwelcome attention.

Gol D. Roger was able to follow the passage because he could hear "the voice of all things", and was able to uncover the path. Though Roger told Whitebeard the story behind the Will of the D., he and his crew seemed to have kept the details of the history a secret, although due to the dangers the remaining crew members possessed, the Marines could not let the crew simply walk away when they were discovered. However, it is unknown if they know about the crew's knowledge of the Void Century or whether this was because of the strength of the crew itself.

The Kozuki Family passed down the knowledge of how to read Poneglyphs within their family up to Kozuki Oden's generation. Also a member of Roger's crew, Kozuki Oden is known to have journeyed to Raftel and like Roger would have been capable of reading the Rio Poneglyph. Oden was killed by Kaido and the Shogun of Wano Country after he refused to tell Kaido a secret he knew (presumably either the location of Raftel, One Piece, knowledge of what was written on the Rio Poneglyph, or how to read Poneglyphs), preventing Oden from passing on the knowledge to how to read Poneglyphs to his son, Kozuki Momonosuke, thus leaving Robin as the only known person left able to decipher the ancient text.

Due to its ties with the Kozuki, the Mokomo Dukedom is shown to be somewhat knowledgeable about Poneglyphs despite being unable to read them, as they are aware of the existence of the Road Poneglyphs and Nekomamushi reveals that it is possible to copy a Poneglyph's message onto a gyotaku, revealing that it is possible to copy the information written on a Poneglyph and record it onto a different medium, albeit one that lacks the Poneglyph's indestructibility.

List of Known Poneglyphs:
So far, Poneglyphs can be divided into three types that deal with the knowledge they contain: History, Instruction and Road

Rio Poneglyph
According to Robin, the Rio Poneglyph (真の歴史の本文（リオ・ポーネグリフ）) is the message carried by all the poneglyphs along the Grand Line. It contains the true history of the One Piece world (including the "Void Century" of which research is forbidden). In order to find it, one must take all other passages from the other Poneglyphs with them on their travels. Gol D. Roger seemed to have accomplished this task, according to Rayleigh, though it is uncertain if the other members of the Roger Pirates know the world's history. According to Tamago the Rio Poneglyph is in fact composed of only nine poneglyphs scattered all over the world.

Record of the Void Century
800 years ago, in the Wano Country, a clan of stonemasons known as the Kozuki Family invented indestructible stone blocks with the purpose of carving important, ancient text on them in order to record history while also preventing it from being destroyed. Those stone blocks would then become the poneglyphs.

The stones were written to preserve the events of the Void Century. After the Void Century ended, the stones were left in the guardianship of the ancients' descendants, who guard them from people who seek to destroy them. The World Government, in an attempt to cover up the previous 100 years made it a global crime to research and decipher poneglyphs. However, this did not stop others from gaining possession of poneglyph knowledge, taking to applying paper to the stones and creating surface transfers of their cryptic language in the hope someone would know how to read it, or stealing the stones themselves and holding possession of them to oneself to gain superiority over those looking for them.

Gol D. Roger's attempt
I have come here and will lead this passage to the farthest ends of the world.

Roger managed to successfully follow the path of the Poneglyphs and decipher their meanings, leaving at least one message along the way to encourage others to follow his path. However, his crew, although they knew the true history, chose not to awaken any of the ancient weapons.

It is known that Roger had a member of the Kozuki Family, the inventors of the poneglyph, within his crew: the daimyo Kozuki Oden, who also witnessed the true history.

The Demons of Ohara
The researchers on Ohara decided to study their island's Poneglyphs in an attempt to discover the missing history of the world. However, they were limited by the greater lack of access and knowledge of the Poneglyphs and sent out researchers to find more information on them, knowing the study of the Poneglyphs were illegal.

Nico Olvia along with thirty-three other archaeologists, set out to sea. Sadly, their attempt failed and they were intercepted by the Marines leaving only Olvia as the sole survivor. On board the ship they found information which allowed the Marines to trace Olvia's origins back to Ohara and CP9 unit was sent to investigate. The World Government had always been against the scholars because of their knowledge but researching the Poneglyphs meant they had an excuse to act against them.

Olvia escaped the Marines thanks to the help of Jaguar D. Saul and managed to return to Ohara in time to warn her comrades about the Marines heading their way. However, CP9 had already arrived on the island and a Buster Call attack commenced after Clover revealed that he had discovered the knowledge held by the Ohara Island Poneglpyh. Ohara was destroyed, wiping out the entire Island and all of its inhabitants with the exception of Nico Robin, who managed to flee in the process, leaving the fate of the Ohara Poneglyph a complete mystery.

During her time on the run, Robin was known to have deciphered at least one poneglyph and researched constantly into finding others.

Alabasta
Crocodile targeted the Alabasta Kingdom because of its Poneglyph, which was known to contain information on the whereabouts of Pluton. He then went about creating the Baroque Works syndicate in an attempt to bring down the Alabasta Kingdom and claim Pluton. He employed Robin to read the Poneglyph of Alabasta.

When Robin finally got the chance to read this Poneglyph, however, Robin lied about its contents, which caused Crocodile to turn against her. Due to the battle between Monkey D. Luffy and Crocodile, when the fight ended the Royal Tomb where the Poneglyph was held became unstable and began collapsing around them. Robin was saved by Luffy along with King Nefertari Cobra, however the Poneglyph was buried in the process.

Skypiea
Robin traveled with the Straw Hats, claiming Luffy was responsible for her continued existence. During her time she traveled with the Straw Hat Pirates to Skypiea where two more poneglyphs were held. The first held the details of where to find the second, the second contained details about Poseidon and a message written by Gol D. Roger telling further researchers to keep going forward. According to Gan Fall, he had no idea how Roger managed to reach the poneglyph on top of Giant Jack or when he did the feat itself. Robin informed the Shandia that their duty to protect the stone was over and freed them from their ancestors burden in the process. However, Robin had more questions than answers about Gol D. Roger himself.

Meeting Rayleigh
At the Sabaody Archipelago, Roger's first mate, Silvers Rayleigh, mentioned to Robin during the Straw Hats' meeting with him that he knows what the Void Century is and solved the mysteries of the poneglyphs. He admits that saying what it is would take away the impact or any further interpretations of the lost history. He tells Robin to search out the poneglyphs and draw her own conclusions regarding the history. He offered Robin the chance to hear the information from him, however, she declined his offer and chose to continue to find the poneglyphs for herself.

Fishman Island
After arriving at the Sea Forest, Robin read the poneglyph and discovered that engraved on it was an apology letter from a man known as Joy Boy to the Mermaid Princess Poseidon.

Zou
When Jack and the Beasts Pirates invaded Zou to look for Raizo of Wano Country, the Mink Tribe chained him to a red poneglyph in a secret area inside the whale-shaped tree to keep him from showing himself. Seventeen days later, the Straw Hats, Trafalgar D. Water Law, and Raizo's samurai comrades freed him from the poneglyph. Robin noted its red color, and Duke Inuarashi explained that it apparently had a different purpose. Robin then got permission to read it.

After Robin deciphered the poneglyph, Inuarashi explained that it was one of the four Road Poneglyphs, and when brought together, they reveal the location of Raftel.

Reverie
Nefertari Cobra and his daughter Vivi leave Alabasta to attend Reverie. Despite his ill health, Cobra wishes to attend, as he plans to ask the World Government about poneglyphs, something he has intended on asking them ever since his encounter with Nico Robin.

Anime and Manga Differences
The first artifact to actually be recognized as a poneglyph was seen in Alabasta in Episode 123.

Another poneglyph was seen in Episode 102, also in Alabasta, when Luffy, Zoro, and Chopper were lost in the desert and fell through the top of an ancient ruin where a poneglyph was seen half buried in the sand. However, it bears no significance to the series, since it was shown in a filler episode.

Trivia

 * Tamago claim that there are about thirty poneglyphs in the world. Coincidentally, most of the poneglyph shown by that point in the series where hidden:
 * The Alabasta Poneglyph is hidden underground, below the Tomb of the Kings.
 * The Shandorian are on a location that is called a lie or a myth.
 * The one on Ohara was seized by the World Government and its existence was covered up by them as well.
 * Zou's Road Poneglyph is hidden in the whale tree.