Panorama of the Grampians National Park from the Pinnacle, Victoria, Australia. The Grampians are a series of five spectacular sandstone ridges running north to south with steep and craggy slopes on the eastern side and gentler slopes to the west. They are the result of earth movements lifting and tilting the hard sandstones creating an impressive landscape of peaks and valleys. The Pinnacle is probably the most visited lookout in the park due to a spectacular outcrop and views over Halls Gap.