The Last of the Zoroastrians, Towers of Silence

Far removed from Tehran's bustling tin-roofed teashops and Isfahan's verdant pomegranate gardens, the deserts known as Dasht-e Kavir and Dasht-e Lut meet at the city of Yazd, once the heart of the Persian Empire.

Walking across the wind-whipped plains of the forgotten city, a young Iranian woman dressed in colorful floral garbs points out a sand-dusted tower hovering in the distance like a dormant volcano under a relentless sun. "This is where we put tens of thousands of corpses over the years," she explains with a congenial smile.

The funerary tower is part of the ancient burial practice of Zoroastrianism, the world's oldest monotheistic religion. Zoroastrians (known in India as Parsis) regard sky burials, in which the bodies are exposed to natural elements including vultures in open-topped "Towers of Silence," as an ecologically friendly alternative to cremation, consistent with their religion's reverence for the earth. A Zoroastrian priest clad in a long, cotton robe explains: "Death is considered to be the work of Angra Mainyu, the embodiment of all that is evil, whereas the earth and all that is beautiful is considered to be the pure work of God. We must not pollute the earth with our remains."

The priest believes that open burials are a fulfillment of the central tenet of his religion, which is to practice good deeds. With a forlorn expression, he notes that, 3,000 years after the tradition of open burials began, there are not enough Zoroastrians left alive to keep the tower in Yazd open. Instead, today's Zoroastrians who want to observe traditional burial practices must request in their will that their body is sent to a forested suburb in Mumbai, India, where the last Tower of Silence still operates. ...

via The Last of the Zoroastrians - TIME.

From Wikipedia:

Towers of Silence are circular, raised structures used by Zoroastrians for exposure of the dead. There is no standard technical name for such a construction. ...

Zoroastrian tradition considers a dead body—in addition to cut hair and nail-parings—to be nasu, unclean, i.e. potential pollutants. Specifically, the corpse demon (Avestan: nasu.daeva) was believed to rush into the body and contaminate everything it came into contact with^[1], hence the Vendidad (an ecclesiastical code "given against the demons") has rules for disposing of the dead as "safely" as possible.

To preclude the pollution of earth or fire (see Zam and Atar respectively), the bodies of the dead are placed atop a tower—a tower of silence—and so exposed to the sun and to birds of prey. Thus, "putrefaction with all its concomitant evils" "is most effectually prevented."^[2]

The towers, which are fairly uniform in their construction, have an almost flat roof, with the perimeter being slightly higher than the center. The roof is divided into three concentric rings: The bodies of men are arranged around the outer ring, women in the second circle, and children in the innermost ring. Once the bones have been bleached by the sun and wind, which can take as long as a year, they are collected in an ossuary pit at the center of the tower, where—assisted by lime—they gradually disintegrate and the remaining material—with run-off rainwater—runs through multiple coal and sand filters before being eventually washed out to sea. The ritual precinct may only be entered by a special class of pallbearers, called nasellars, a contraction of nasa.salar, caretaker (-salar) of potential pollutants (nasa-).

Okay, technically, I don't know why this is any worse than a ground burial, but it does give me the creeps. I'm surprised no major US horror films have duplicated something like this as a movie set. Creeeeepy.