"It's surprising to see garbage littered here and there in this fragile ecosystem," Aditya Gosh, a tourist from Kolkata, remarked.
"It seems the tourists here leave everything except footprints," Ghosh told IANS, while pointing towards non-biodegradable waste dumped carelessly along the banks of the glacial-fed Beas river near Marhi, en route to the Rohtang Pass from Manali, located at an altitude of 13,050 feet and 52 km from here,
His wife Pragya was horrified to see the amount of garbage like polythene and paper bags, empty beer and liquor bottles, food sachets and clothes dumped carelessly in the mountains.
"I think this highly sensitive ecosystem has failed to catch the attention of Modi's clean-up campaigns," she said.
The picturesque Rohtang Pass, located in the Pir Panjal range, is a major attraction for both domestic and foreign tourists.
According to the tourism department, more than 100,000 tourists visit the Rohtang Pass every year and tourism, including skiing, trekking and paragliding, is a key source of income for the local people.
For more than five months from December, the pass remains cut off from the rest of the country due to heavy snowfall.
No volunteer of 'Swachh Bharat Mission' has ever visited this area, said Ravi Thakur, who sells eatables at the Rohtang Pass.
He said the local administration has installed waste disposal and drop off points between Marhi and Rohtang Pass but visitors ignore them.
Studies by the G.B. Pant Institute of Himalayan Environment and Development in Kullu town near here said the eco-system of the Rohtang Pass is being damaged by the increasing tourist inflow and exhaust fumes of vehicles.
They say more than 2,000 vehicles go over the pass every day during peak tourist season. A major component of the traffic is also defence vehicles, with the forces reaching supplies to strategic points through the pass.
The deteriorating ecology of Rohtang, meaning "piles of dead bodies" in Persian, has also caught the attention of the National Green Tribunal (NGT).
It has directed the government to check unregulated plying of vehicles and imposition of fee on every individual and vehicle crossing the Rohtang Pass, besides construction of an eco-friendly toilet and installation of garbage collection bins en route.