The ancient script of the Indus Valley civilization that remains undeciphered to this day is known as the Indus script. Used around 2600-1900 BCE in the Indus Valley, it appears on seals, pottery, and various artifacts. Despite numerous attempts by epigraphers and linguists to decode it, the script's symbols have yet to yield a definitive understanding of its language and meaning. The Indus Valley civilization remains one of the great mysteries of ancient history, and the undeciphered script complicates our knowledge of their society, governance, and culture.