Niah National Park, located within Miri Division, Sarawak, Malaysia, is the site of the Niah Caves, a limestone cave and archeological site. Niah National Park was 31.4 km² when it was gazetted in 1974.Nomination for World Heritage status of the Niah Caves was sent to UNESCO in 2010.

Alfred Russel Wallace learned about the caves during his 1855 expedition to Borneo. He wrote about the caves as a potential site for discovering important hominin fossils in a letter to Charles Darwin. British archaeologists excavated the site in 1869-1870, but failed to make significant discoveries and abandoned the site.

In the 1950s and 1960s, Barbara and Tom Harrisson excavated the site and made significant discoveries. They discovered the Deep Skull in 1958.

Since then local universities and foreign scientists have continued the archaeological research, and many articles have been published in the Sarawak Museum Journal. The site has been re-excavated (1999–2003+)[4] by The Niah Caves Project (NCP), a joint British-Malaysian expedition, to determine the accuracy of Harrisson's work.