16 artifacts in this category
The Antikythera Compass of China
The south-pointing chariot is an ancient Chinese mechanical device that maintained a constant directional reference regardless of which way the chariot turned — using a differential gear mechanism, not a magnetic compass. A figure on top of the chariot always pointed south. The differential gear principle it used was not independently discovered in the West until the 19th century. Chinese legend attributes its invention to the Yellow Emperor in 2600 BCE.
The Linear A Script
Linear A is the undeciphered writing system of the Minoan civilisation of Bronze Age Crete. Despite being the predecessor of Linear B (which was deciphered in 1952), Linear A has resisted all attempts at translation for over 120 years. It appears on clay tablets, stone vessels, and metal objects across the Aegean. The language it encodes is completely unknown — it may be the only major Bronze Age language that will never be deciphered.
The Indus Valley Script
The Indus Valley Civilisation — the largest of the ancient world's four great civilisations, covering an area larger than Egypt and Mesopotamia combined — left behind over 4,000 inscribed objects bearing an undeciphered script. Despite over a century of attempts by linguists and cryptographers worldwide, the Indus script has never been decoded. We know nothing of the language, religion, or history of a civilisation that housed over 5 million people.
The Rongorongo Script of Easter Island
Rongorongo is an undeciphered script found on 26 wooden tablets from Easter Island. It is one of only three or four writing systems in human history to have been invented independently — yet it appeared on an isolated Pacific island with no known contact with literate civilisations. When European missionaries arrived in 1864, they found the islanders using the tablets for rituals but unable to read them. The last people who could read Rongorongo died in the 19th century.
The Olmec Cascajal Block
The Cascajal Block is a serpentinite tablet bearing 62 symbols that represent the oldest known writing in the Americas, dating to approximately 900 BCE. It predates the previously oldest known Mesoamerican writing by 400 years. The symbols appear in a linear sequence consistent with a true writing system, but the script has not been deciphered. It confirms that the Olmec — the 'mother civilisation' of Mesoamerica — had writing.
The Dispilio Tablet
A wooden tablet discovered in a Neolithic lake dwelling in Greece, carbon dated to 5260 BCE, bears inscribed symbols that some researchers identify as an early form of writing — predating Sumerian cuneiform by over 1,000 years. If genuine writing, it would overturn the established timeline of human literacy. The symbols resemble those of the Vinča culture, which produced thousands of inscribed objects across the Balkans between 5500 and 3500 BCE.
The Nimrud Lens
A 2,700-year-old piece of polished rock crystal discovered in the ruins of the Assyrian palace at Nimrud, Iraq. It has a focal length of approximately 11 cm, making it a functional magnifying lens. If the Assyrians possessed optical technology, it could explain how ancient craftsmen produced the extraordinarily fine detail found on Assyrian cylinder seals — detail that appears to require magnification to create.
Al-Jazari's Programmable Robot
In 1206 CE, the engineer Al-Jazari described and built a programmable humanoid robot band — four musicians on a boat whose movements were controlled by a rotating drum with pegs that triggered levers. It is the earliest known programmable automaton, predating modern robotics by 800 years. Al-Jazari also invented the crankshaft, the camshaft, and the combination lock.
Tartaria Tablets
Three small clay tablets found in Romania bearing inscribed symbols that some researchers argue predate Sumerian writing by 1,000 years — potentially making them the world's oldest writing. If genuine, they would overturn the established history of writing. The tablets were found with the burned bones of an elderly woman.
Phaistos Disc
A fired clay disk from the Minoan palace of Phaistos bearing 241 impressions of 45 distinct symbols arranged in a spiral. It is the world's oldest known printed document — the symbols were made with pre-formed stamps, not carved individually. The language and meaning remain undeciphered after 115 years.
Inca Quipu
The Inca Empire administered millions of people across 4,000 kilometers of coastline without a writing system — using quipus instead. These knotted cord devices recorded census data, tax records, and astronomical information. Recent research suggests some quipus may encode narrative text, not just numbers, potentially making them an undeciphered writing system.
Rongorongo Script
An undeciphered script found on Easter Island that may be one of only three or four writing systems invented independently in human history. Only 25 objects bearing the script survive. The Rapa Nui people had no contact with literate civilizations, yet developed a complex writing system. The script has never been deciphered.