Jim Jim Falls is a 200 m (660 ft) high waterfall located in the Kakadu National Park, in the Northern Territory, Australia. It is believed that 140 million years ago much of Kakadu was under a shallow sea. The prominent escarpment wall formed sea cliffs and the Arnhem Land plateau formed a flat land above the sea. Today the escarpment, which rises to 330 metres (1,080 ft) above the plains, extends over 500 kilometres (300 mi) along the eastern side of the Park and into Arnhem Land.