Between 2003 and 2009, a french-indonesian research program has conducted surveys in the Gunung Gergaji karstic mountains (East Kalimantan, kabupaten Kutai Timur), where several caves adorned with rock art have been discovered. Among the sites surveyed, Liang Jon is a vast rockshelter (c. 30 m x 15 m) located on the left bank of the river Marang. In 2005, two test-pits (A and B) were conducted which led to the discovery of several structures, including a human inhumation and a deposit of fragmented human bones.