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At the entry checkpoint, the road narrows to about six metres wide – enough for two small cars to pass one another slowly, but anything larger than a pickup truck must move in single file.
The stony mountains on either side soar more than 600 metres into the air at a steep incline. It takes a keen eye to spot the snipers positioned between jagged peaks, but there is plenty of time to look for them; every vehicle is stopped and searched by the men who guard the checkpoint. Every rifle scope is trained on the people who wish to enter.
The Taliban militants have taken nearly every scrap of land in the country over the past fortnight.
But Panjshir, meaning “five lions” in Persian, is a natural fortress.
Despite its proximity to Kabul, no government – foreign or Afghan – has ever taken and held it by force. Panjshiri leaders have always made it clear, for better or worse, that the valley is part of Afghanistan on its own terms.
Today, as far as they are concerned, it is all that is left of Afghanistan.
The Taliban have not attempted to take it, and a source familiar with the Panjshiri leadership’s plans said locals are not worried about any possible incursion.
“All they [the Taliban] can do is watch,” they said.
The Lion of Panjshir
There is no greater symbol of the ferocity and independent spirit that Panjshir’s leaders have sought to project than Ahmad Shah Massoud, an anti-Soviet then anti-Taliban resistance commander known as the “Lion of Panjshir”.
He was assassinated two days before 9/11 by Tunisian agents of Al Qaeda, who posed as reporters from the Qatari news channel Al Jazeera and killed him using a bomb hidden in their camera.
Ahmad Shah Massoud remains a controversial figure in Afghanistan. During the country’s civil war in the 1990s, his men are suspected of committing atrocities.
But a mythology has grown up around his exploits. His portrait is ubiquitous in Kabul and many other parts of the country, and he bears the posthumous title of “national hero”.
Ahmad Shah Massoud’s mantle has been taken up by his son, 32-year-old Ahmad Massoud, who read war studies at King's College London and received military training from the British Army at Sandhurst.
Footage circulating on social media showed him arriving in the valley shortly after the fall of Kabul, promising to command an anti-Taliban resistance and uphold what is left of the Afghan constitution.
He is thought to have been joined by Amrullah Saleh, who was vice president under Ashraf Ghani – who fled the country on Sunday night.
On Tuesday, Mr Saleh used social media to invoke the Afghan constitution in order to declare himself President.
“In the absence, escape, resignation or death of the President, the First Vice President becomes the caretaker President,” he wrote. “I am currently inside my country and am the legitimate caretaker President.”
Mr Saleh may be in the country, but the circumstances nonetheless render him a president-in-exile.
On maps of territorial control in Afghanistan, Panjshir appears as a lonely island, surrounded on all sides by the new order.
The Taliban has consolidated its hold on the national government, taking over all of the country’s federal institutions and initiating talks with Afghanistan’s neighbours, most of whom have already indicated they will establish formal relations with the Taliban government.
This means the Panjshiris, who in past civil wars have relied on foreign support – mainly from Iran, India and the West – are more isolated than ever.
An ex-senior Afghan government official, now based overseas, said that while the Panjshiris can continue to hold the valley indefinitely, it was less clear how long they will be able to sustain a political stalemate.
Any Taliban effort to overcome them is likely to result in a demoralising slaughter for the Taliban, but it is not in the Panjshiri leaders’ nature to sit out on the national conversation forever.
The Taliban, the former official said, will eventually try to entice them to join the government, and pressure from Afghanistan’s neighbours to see a true “unity government” may eventually force them to concede.
In the meantime, the Panjshiris are discussing among themselves a detailed list of demands with which they might enter any negotiation with the Taliban, should they decide to do so, the source familiar with their thinking tells me. They have also sought to balance the terms of any future engagement by accumulating as much hard power as they can.
“When Kabul fell, the Panjshiris took attack helicopters and armoured vehicles from the provinces into the valley,” the source said. They have been joined there by several Afghan Special Forces commanders who refuse to surrender to the Taliban, they said.
The Panjshiris have also sought to brand their province as a kind of sanctuary, reportedly taking refugees from elsewhere in the country, provided they can get past Taliban lines and on to the valley road.
The province’s commanders are also thought to be preparing its young men for any future battles, raising a new generation of “lions”.
‘Do not romanticise Panjshir’
One Afghan student abroad whose family remains in Panjshir warned against romanticising the valley, and fears that by doing so the media may provoke the Taliban into attempting to take it by force.
That is unlikely, but there are other reasons to avoid painting too idealistic a picture of this besieged resistance force.
As much as they have earned their near-mythical status in Afghanistan’s military history, the reality is that the position of Panshir’s commanders has never been more precarious.
Their willingness to explore a diplomatic end to their situation suggests that they know this, too, even if they feel they can set the terms.
While they have yet to publish any official statement, a source familiar with their conversations said they have given him one message to pass on to the Taliban: “Form an inclusive government. In the meantime, do not try to enter the valley.”