High in the hills of western India, Homi Dhalla looks around the Bharot Caves complex, pointing out the cracked and crumbling stone in the roughly-hewn rocks.
"If we wish to save these caves, the world community has to stand up and do something about it now before it’s too late," he says, as the web video fades to a still image of two Parsi priests worshipping in one of the stark grey vaults.
Time and neglect have left the ancient caves in a dangerous state of disrepair that now threatens them as a place of pilgrimage for India’s fire-worshipping Parsi community.
In the 14th century, their ancestors fled to the caves with the sacred fire of their Zoroastrian religion to escape a Mughal invasion.
According to legend, the "Iranshah" — the first fire to be consecrated in India — stayed lit throughout the 12 long years they were there.
So far, 3,000 people have signed a petition on the www.zoroastrians.net portal — where Dhalla’s video is shown — which will be sent to the Archaeological Survey of India, urging it to repair the protected caves.
"If we have 7,000 to 8,000 (signatories) I will be happy," Dhalla, the founder-president of the World Zarathushti Cultural Foundation, told AFP at his home in Mumbai.
"There is an urgent need to conserve the caves for posterity without delay or else this sacred heritage will be lost forever."
Whether the caves near Sanjan, close to the state border of Maharashtra and Gujarat, survive or collapse further into the hillside is not just dependent on funding.
The project — and others like it — more than anything depends on people.
Zoroastrians, who follow the prophet Zarathustra and worship Ahura Maza as the creator of the universe, fled persecution in ancient Iran and arrived in India in the 10th century.
They have risen to prominence over the centuries as industrialists, philanthropists, teachers, musicians, artists and writers in India and abroad.
Famous Parsis include the Tata family, which owns one of India’s most successful business houses, the conductor Zubin Mehta and the late Queen singer Freddie Mercury.
But the population of India’s most successful and celebrated minority has been in steady decline, with numbers down to just under 70,000 in India, according to the last census in 2001.
As the birth rate falls and Parsis marry outside the community or migrate, experts say they face a race against time to catalogue the distinctive religion and culture for future generations.
Kainaz Amaria has seen the decline first hand, particularly in rural areas where once-thriving Parsi communities have died out and their homes and fire temples now lie abandoned.
The 32-year-old photojournalist, who comes from a family of Indian Parsi priests, arrived in Mumbai last year and has been documenting everything from wedding ceremonies to water rituals in the close-knit community.
"I like to focus on the customs and the cultures and the traditions that are typically Parsi," said Amaria, who is in India on the US government’s Fulbright scholarship programme as part of her masters degree in visual communication.
Comparing her experience growing up on the US west coast and Parsi life in India, she said all it took was her parents to emigrate and one generation for some rituals to disappear.
"If they’re not documented they’ll fade away," she said. "This is my little way of giving something back to the community. I feel a very strong sense of responsibility."
The decline in Parsi numbers doesn’t mean that nothing has been done to preserve tradition.
A Zoroastrian Information Centre has been built at the coastal town of Udvada in Gujarat, where the "Iranshah" still burns at one of the most important Parsi fire temples in the world.
The UNESCO-backed Parzor project has saved damaged or decayed ancient manuscripts at the Meherjirana Library in nearby Navsari and transferred them onto microfilm.
It is also recording oral history and charting the lives of famous Parsis while scholars from around the world are taking an increased interest in the endangered Parsi-Gujarati dialect.
Dhalla has led archaeological digs in Sanjan, where the first Zoroastrians settled, and unearthed artefacts shedding light on their trading past.
His foundation’s other areas of concern include recording and reviving religious chants and traditional Parsi songs, calligraphy and promoting the community’s linguistic heritage.
Other work includes new breeding programmes for vultures, which Parsis depended on to eat their dead on "Towers of Silence" before bird numbers plummeted to near extinction in India.
But the head of the Parzor project, Shernaz Cama, sounded pessimistic as she told of lost skills such as traditional Parsi embroidery.
"Whatever one is trying to do it’s a race against time," she said. "This has been our biggest problem."