Disposal of human corpses, also called final disposition, is the practice and process of dealing with the remains of a deceased human being. Disposal methods may need to account for the fact that soft tissue will decompose relatively rapidly, while the skeleton will remain intact for thousands of years under certain conditions. Several methods for disposal are practiced. A funeral is a ceremony that may accompany the final disposition. Regardless, the manner of disposal is often dominated by spirituality with a desire to hold vigil for the dead and may be highly ritualized. In cases of mass death, such as war and natural disaster, or in which the means of disposal are limited, practical concerns may be of greater priority. Ancient methods of disposing of dead bodies include cremation practiced by the Romans, Greeks, Hindus, and some Mayans; burial practiced by the Chinese, Japanese, Bali, Jews, Christians, and Muslims, as well as some Mayans; mummification, a type of embalming, practiced by the Ancient Egyptians; and the sky burial and a similar method of disposal called Tower of Silence practiced by Tibetan Buddhists, some Mongolians, and Zoroastrians. A modern method of quasi-final disposition, though still rare, is cryonics; this being putatively near-final, though nowhere close to demonstrated. Commonly practiced legal methods Some cultures place the dead in tombs of various sorts, either individually, or in specially designated tracts of land that house tombs. Burial in a graveyard is one common form of tomb. In some places, burials are impractical because the groundwater is too high; therefore tombs are placed above ground, as is the case in New Orleans, Louisiana, US. Elsewhere, a separate building for a tomb is usually reserved for the socially prominent and wealthy; grand, above-ground tombs are called mausoleums. The socially prominent sometimes had the privilege of having their corpses stored in church crypts. In more recent times, however, this has often been forbidden by hygiene laws. Burial was not always permanent. In some areas, burial grounds needed to be reused due to limited space. In these areas, once the dead have decomposed to skeletons, the bones are removed; after their removal they can be placed in an ossuary. Ground burial A ground burial is usually accomplished by excavating a pit or trench, placing the deceased and objects in it, and covering it over. Humans have been burying their dead for over 100,000 years of civilization. Burial practices