SRINAGAR, India - Every summer for two months, hundreds of thousands of devout Hindus, some chanting hymns, trek high into the Himalayas in Indian Kashmir in a gruelling pilgrimage to a cave shrine.
Surrounded by clouds and 3,800 metres (12,800 feet) above sea level, the Amarnath shrine is one of Hinduism's most revered sites. But the debris left behind is anything but sacred.
By the end of the 55-day pilgrimage season, rubbish, including plastic bottles and bags, as well as human waste, can be found strewn across the mountain trails that wind through the fragile Himalayan environment.
Some of the rubbish falls into melted glaciers rushing through the valleys, threatening a vital source of drinking water for thousands of people who live downstream, experts said.
"There are more than 53 glaciers in that area," said Professor Shakil Ramshoo, who heads the earth sciences department at the University of Kashmir.
"Huge quantities of fecal matter and waste generated from the many eateries directly finds its way into the water bodies, deteriorating the water quality," he added.
The government and pilgrimage organisers insist they continuously improve measures to protect and preserve the environment. Sewage systems have been installed at the start of the mountain paths and a number of composting toilets have been set up - on a trial basis - along the way.
But management of the area is a source of tension in the Muslim-majority region.