In the Zoroastrian rite, circular stone platforms or towers erected on hills, on which the dead are placed. Typical examples are tall structures, built of stone or brick, and having gratings on which the dead are left. After the corpses have been devoured by vultures, the bones fall into a pit below, thereby satisfying the Zoroastrian injunction that corpses, which are seen as extremely polluting, should not defile the earth or have contact with fire. Towers are seen as threats to purity and can be entered only by professional corpse-bearers.
