The Grampians National Park in Victoria was created in 1984 and includes four mountain ranges. These ranges are composed of sandstone which was created around 400 million years ago when sand was deposited in a shallow sea. Over time these deposits were compressed and hardened and subsequent earth movements tilted and raised the sandstone beds. Erosion has left the hardest sandstone layers exposed as tall cliffs - of of the tallest and longest cliffs in the Grampians is at Mt Rosea. The summit is poised on the cliff edge and being one of the higher peaks it provides an extensive view of the national park.