Mohenjo-daro, Harappa and their civilization, vanished without trace from history until discovered in the 1920s. It was extensively excavated in the 1920s, but no in-depth excavations have been carried out since the 1960s.
Mohenjo-daro is a UNESCO World Heritage Site. The most extensive recent work at the site has focused on attempts at conservation of the standing structures, undertaken by UNESCO in collaboration with the Department of Archaeology and Museums, as well as various foreign consultants.
In December 1996, preservation work at the 500-acre site suspended after funding from the government and international organisations ran out, according to a resident archaeologist.
However in April 1997, the UN Educational, Scientific and Culture Organisation (UNESCO) funded $10 million to a project to be conducted over two decades in order to protect the Mohenjo-daro ruins from flooding. This project has been a success so far. UNESCO's efforts to save Mohenjo-daro was one of the key events that led the organization to establish World Heritage Sites.