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 Type
Poneglyphs are massive blocks made of an indestructible type of stone. They have text written in an ancient language carved on them. There are a total of three types of Poneglyphs scattered across the world; Historical, Instructional and Road Poneglyphs:
- "Historical Poneglyphs" reveal pieces of ancient history as well as messages written by ancient people.
- "Instructional Poneglyphs" contain instructions and/or clues about the locations of Historical Poneglyphs.
- "Road Poneglyphs" (ロード歴史の本文（ポーネグリフ） Rōdo Pōnegurifu?, literally meaning "Road Text of History") detail a location. The combined locations detailed by all four Road Poneglyphs, allows one to locate Raftel.
- Rio Poneglyph (真の歴史の本文（リオ・ポーネグリフ） Rio Pōnegurifu?, literally meaning "True Text of History"), according to Robin, is the message carried by all the Poneglyphs along the Grand Line. It contains the true history of the 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. According to Tamago, the Rio Poneglyph is in fact composed of only nine Poneglyphs.
Both Historical and Instructional Poneglyphs are dark blue in color, while the Road Poneglyphs are deep red in color.
Each Historical Poneglyph tells a piece of history long forgotten. This history includes mentions of three weapons of mass destruction: Pluton, Poseidon and Uranus. In the eyes of the World Government, they are dangerous artifacts; however, despite the World Government declaring the Poneglyphs 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 treasure located on Raftel: two of the Yonko, Charlotte Linlin and Kaido, have each claimed possession of a Road Poneglyph.
The stones are left in the care of the descendants of ancient civilizations, as seen in both Alabasta and Shandora. The Shandorian Poneglyph was a fiercely guarded treasure of the Shandian people, and they felt a deep visceral connection to it - particularly the bell built around it - that was passed down 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, thus relieving them of their centuries-long duty.
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 inferred by Robin in her conversation with the King of Alabasta, Nefeltari Cobra, when she scoffs at and rebukes his statement about a hereditary charge of the monarchy to "protect" the stone, though he was truthfully unaware of the deeper reasons or motives of its concealment decided long before his time.
Gol D. Roger managed to follow the passage of the Poneglyphs because he could hear "the voice of all things", and thus uncovered the truth of the Void Century with his crew; however, Silvers Rayleigh notes that they may have interpreted what they learned incorrectly because they did not possess the intellect of Clover or the other scholars of Ohara.
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, Oden journeyed to Raftel with him and, like Roger, could decipher 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, and leaving Robin as the only known individual who can decipher the ancient text.
Due to its ties with the Kozuki Family, the Mokomo Dukedom is 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, simultaneously proving that it is possible to copy the information written on a Poneglyph and record it on a different material, albeit one that lacks a Poneglyph's indestructibility.
List of Known Poneglyphs:
Poneglyphs can be divided into three types that deal with the knowledge they contain: Historical, Instructional, and Road.
|Ohara||Located in the basement of the Tree of Knowledge, this Poneglyph includes information about the Void Century, including the name of the Great Kingdom.|
|The Tomb of the Kings within Alubarna, Alabasta||This Poneglyph details the location of Pluton. According to Nefeltari Cobra, his family has protected the stone for centuries, though Robin implies that they were actually hiding it from the people and the World Government.|
|Sea Forest of the Ryugu Kingdom, Fishman Island||Nico Robin initially believed that this Poneglyph held vital information to understanding the Void Century; however, upon finding it, she noted that it was different than the other Poneglyphs she had found, reading more like an apology letter than a historical text. The message was written by a man from the surface known as "Joy Boy". In the message, he apologizes to the people of Fishman Island for breaking his part of a promise, which involved returning to Fishman Island to carry out Noah's purpose.|
|Golden Belfry of Shandora||Located at the base of the Golden Belfry, this Poneglyph details the location of another ancient weapon, Poseidon. It was protected by the Shandian people for centuries until Robin deciphered it.|
|The ruins of Shandora||Ancient text identical to that of the Poneglyphs is inscribed on a wall within a set of ruins in Upper Yard; upon reading it, Robin discovers that it relays cryptic instructions regarding the Golden Belfry. However, Robin did not refer to the wall as a poneglyph, so it is unknown if it is considered one.|
|The Whale Tree, Zou||Hidden within the Whale Tree, this Road Poneglyph contains information that, when combined with the information on the other three Road Poneglyphs, will reveal the location of Raftel.||Zou's Road Poneglyph.|
|The Room of Treasure, Totto Land||
This Road Poneglyph is currently within the possession of Charlotte Linlin and her crew. Due to the Sanji Retrieval Team's invasion of Totto Land, it is now heavily guarded within the Room of Treasure. A copy of it is currently in the Straw Hat Pirates' possession. 
|Under jurisdiction of the Beasts Pirates|
This "Road Poneglyph" is currently considered lost.
|Poneglyphs of Unknown Purpose|
|Unknown||While she was on the run as a pre-teen, Robin found a poneglyph in a wooded area. Its precise location was not revealed, the poneglyph was not named, and its contents are unknown.|
|Coastal Ruins ‡, with Jinbe ‡|
The Room of Treasure, Totto Land
|This poneglyph was found by locals who showed it to Jinbe after Wadatsumi threw some underwater ruins onto dry land. As Jinbe and Wadatsumi left, they took the poneglyph with them. This poneglyph was later delivered to Charlotte Linlin, which she had placed in her Room of Offerings after the Sanji Retrieval Team invaded Totto Land. A copy of it is currently in the Straw Hat Pirates' possession.|
|The Room of Treasure, Totto Land||Big Mom has acquired a poneglyph through unknown means, and it has been placed under heavy guard alongside her two other poneglyphs in her Room of Treasure following the Sanji Retrieval Team's invasion of Totto Land. A copy of it is currently in the Straw Hat Pirates' possession.|
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 for the purpose of recording important history on them while preventing it from being destroyed. Those stone blocks would 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 descendants of ancient civilizations, who guarded them from people seeking to destroy or claim them. The World Government, in an attempt to cover up the events of the Void Century, made researching and deciphering Poneglyphs a crime punishable by death. However, this did not stop others from gaining possession of Poneglyph knowledge, transferring the cryptic language on the Poneglyphs to paper in hopes of finding someone who can read it, or keeping the stones themselves in their own possession in order to gain superiority over those looking for them.
Gol D. Roger's attempt
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 chose not to awaken any of the ancient weapons detailed in the Poneglyphs.
At some point in time, Roger encountered Big Mom's Road Ponegyph and was able to interpret the characters in order to reach Raftel. 
The Demons of Ohara
The researchers on Ohara decided to study their island's Poneglyph in an attempt to discover the missing history of the world. However, they were limited by lack of access to and knowledge of the other Poneglyphs, and thus sent out researchers to find more information on them, knowing the study of the Poneglyphs was 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 Olvia as the sole survivor. The Marines found information among the belongings of the dead researchers that allowed them to trace the team back to Ohara, and a CP9 unit was sent to investigate. The World Government had always been wary of the scholars because of their knowledge, but researching the Poneglyphs meant they had an excuse to act against them.
Olvia escaped the Marines with 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 Poneglyph in the Tree of Knowledge. 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 mystery.
During her time on the run, Robin deciphered at least one Poneglyph and constantly strove to find others.
Crocodile targeted the Alabasta Kingdom because of its Poneglyph, which contained information on the whereabouts of Pluton, and created the Baroque Works syndicate in an attempt to bring down the Alabasta Kingdom and claim Pluton, employing Robin to read the Poneglyph. When Robin finally got the chance to read this Poneglyph, however, she lied about its contents, which caused Crocodile to turn against her because he no longer needed her. Due to the ferocious battle between Monkey D. Luffy and Crocodile, compounded by an attempt from King Nefeltari Cobra to crush Crocodile underneath the rubble by displacing a pillar, the Tomb of the Kings where the Poneglyph was held became unstable and began collapsing around them. Luffy saved Robin and Cobra, but the Poneglyph was buried in the collapse.
Robin joined the Straw Hat Pirates, claiming Luffy was responsible for her continued existence, and traveled with them to Skypiea where another Poneglyph was held. There was a wall in the Shandorian ruins cryptically describing the location of the Poneglyph in the same runes that the Poneglyphs themselves were inscribed with. The Poneglyph itself, located at the base of the Golden Belfry, contained details about Poseidon and a message written by Roger, telling further researchers to keep going forward. According to Gan Fall, he had no idea when or how Roger managed to reach the poneglyph on top of Giant Jack. Robin informed the Shandia that their duty to protect the stone was over, freeing them from their ancestors' burden.
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 that Roger solved the mysteries of the Poneglyphs; however, he also admitted that saying what it was would take away the impact or any further interpretations of the lost history, due to his crew not being proper historians like the Ohara scholars, before telling Robin to search out the Poneglyphs and draw her own conclusions regarding the lost history. Despite this, Rayleigh offered Robin the chance to hear the information from him, but she declined his offer and chose to continue to pursue the Poneglyphs herself.
When Jack and the Beasts Pirates invaded Zou to look for Raizo of Wano Country, the Mink Tribe chained him to the Road Poneglyph within the Whale 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. When Robin noted its red color, Duke Inuarashi explained that it had a different purpose than the normal blue Poneglyphs did and gave her permission to read it.
After Robin deciphered the Road Poneglyph, Inuarashi explained its purpose of revealing the location of Raftel when its information was combined with that of the other three Road Poneglyphs.
Cobra and his daughter Nefeltari Vivi left Alabasta to attend Reverie. Despite his ill health, Cobra wished to attend because he planned to ask the World Government about Poneglyphs, a desire he has held ever since his encounter with Robin.
Charlotte Linlin's Road Poneglyph became a target of interest for the Straw Hat Pirates when they invaded her country in order to retrieve Vinsmoke Sanji from her clutches.  Brook and Pedro underwent their own side operation to create a copy of the poneglyph while the rest of the crew focused on Sanji, and eventually, Brook was able to break into her poneglyph storehouse and defeat her guards. Linlin subdued him personally for this, and after defeating him, she recounted how she failed to stop Gol. D Roger from breaking into the very same room over twenty years ago to interpret the Poneglyph. 
Linlin also revealed that members of the Three-Eye Tribe have the potential to awaken the ability to "hear the Voice of All Things" just as Roger did, and currently, she is waiting for her daughter Charlotte Pudding (who is a human and three-eye hybrid) to awaken this ability and lead her to Raftel. 
Despite being defeated, Brook is later revealed to have successfully created copies of Linlin's three Poneglyphs, making the Straw Hat Pirates one of the few factions in the world to own one of the Road Poneglyphs.
Anime and Manga Differences
The first artifact to actually be recognized as a poneglyph was seen in Alabasta in Episode 123. However, 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.