Several dozen inscriptions in an unknown writing system have been discovered in an area stretching geographically from Kazakhstan, Uzbekistan and Tajikistan to southern Afghanistan. Most inscriptions can be dated to the period from the 2nd century BCE to the 3rd century CE, yet all attempts at decipherment have so far been unsuccessful.

The recent discovery of previously unknown inscriptions near the Almosi gorge, Tajikistan, however, allows for a renewed attempt at decipherment.