An extremely dangerous cloud, a wall cloud (or pedestal cloud) is a large, lowering cloud formation that develops beneath the base of a cumulonimbus cloud that often forms tornadoes. It is typically beneath the rain-free base (RFB) portion of a thunderstorm, and indicates the area of the strongest updraft within a storm. Wall clouds are sometimes an indication of a rotating mesocyclone in a thunderstorm, and most strong tornadoes form from wall clouds.
The world famous Twelve Apostles are giant rock stacks that rise majestically from the Southern Ocean. They have been created by constant erosion of the limestone cliffs of the mainland that began 10–20 million years ago. The stormy Southern Ocean and constant blasting winds gradually eroded the softer limestone, forming caves and sheer cliffs. The caves eventually became arches and when they collapsed rock stacks up to 45 metres high were left isolated from the shore. Australia.