The Indus Valley Civilization, in its mature phase, thrived for about 700 years, from around 2600 B.C. to 1900 B.C.

The script has remained undeciphered for more than a century. Carved stone seal from the Indus Valley civilization (ca. 2,500 B.C.E.). Photo by DEA/G. Nimatallah/De Agostini via Getty Images.

This map depicts the geographical span of the Indus Valley Civilization (IVC), showing the location of Rakhigarhi (blue), other significant IVC sites (red), and sites to the north and west from ...