Snow sculpture is a sculpture form comparable to sand sculpture or ice sculpture in that it is typically practiced outdoors, and often with people walking by stopping up and watching what is going on. The materials and the tools differ widely, but often include hand tools such as shovels, hatchets, and saws. Snow sculptures are usually carved out of a single block of snow about 6 to 15 feet on each side and weighing about 20 – 30 tons. Snow is perfect for sculpturing when is densely packed. In some cases it is produced by artificial means and in others simply collected from the ground after a serious snowfall.