Towers of silence, known as 'dakhmas,' are circular, raised structures used in Zoroastrianism for the exposure of the dead. This practice is rooted in the core belief that bodies are considered impure after death, and therefore, should not be buried or cremated, as these methods would pollute the earth and fire, both sacred elements in Zoroastrian cosmology. The towers serve as a practical solution to dispose of corpses while respecting the fundamental tenets of the faith.