The shattered gates of the Zawar Kili base are reached after passing dozens of caves - most of their entrances blasted shut by US Daisy Cutter bombs. Ammunition, land mines, and papers are strewn across the dusty terrain. One document gives permission to the Taliban's Southern military commander, Jalaluddin Haqqani, to use a Chinese radio set in his car any time he travels into Pakistan.
It was the first visit to this base by a Western journalist since the US war on terror began. Zawar Kili is the terror base that had been renovated into what was - by far - Al Qaeda's largest base in Afghanistan in recent years.
The US air war had been focused here for the past three weeks, after bin Laden slipped the noose of Afghan proxy fighters and heavy bombing at the Tora Bora base, to the north.
In the past 10 days, some 200 US Marines swept down in helicopters to call in more strikes and begin rooting through the vast network of caves and tunnels. They left hardly a trace when they pulled up stakes Monday morning.
The new battle here to flush out Al Qaeda cells in Paktia, Khost, and Paktika Provinces is, in many ways, a much more challenging military mission than that of Tora Bora - with rewards that might not be as great as the grand prize in that battle: bin Laden himself.
While senior US commanders are not yet saying where they might focus the hunt, there are at least 20 members of a special forces team operating out of the Khost airport near here. And the governor of three mountainous provinces south of Tora Bora, Badshah Khan, says that Al Qaeda cells are operating in three nearby mountain redoubts.
The first, Governor Khan says, is in Spina Shaga, just south of Tora Bora in northern Paktia. It was run by Gulbuddin Hekmatyar during the Afghan war against Soviet aggression.
The second, he says, is only a four-hour drive southwest of the regional capital, Khost. And a third is near Bormal in Paktika province, much farther to the south and bordering on Pakistan's Waziristan tribal area.
"With the current strategy being used by the Americans, the Al Qaeda and Taliban fighters are finding it easy to regroup," says Khan. He claims that his own authority in the region has been undercut by the heavy US bombing raids in recent weeks that have embittered local tribesmen.
The governor, who defends his turf with a passion, does not want more US troops thrown into the hunt for bin Laden - he'd rather use his own. He claims a heavy or permanent US ground contingent could well spark a "civil war."
It was the first time in nearly a decade that Cmdr. Sakhi Jan Wafadar - who, along with his 16 gunmen, served as the guide on this trip - visited Zawar Kili.
A sign in Arabic above the encampment reads: "Prepare your forces for the infidel and know that the Holy War will continue until doomsday."
A few trees in the distance were bare - all their leaves and small limbs incinerated by the intense heat of the blasts.
At the top of the ravine stood two Soviet-era personnel carriers mounted with heavy guns that had been hit by shrapnel. There were antiaircraft guns and artillery overturned by the blasts. A rudimentary sanitation system, a mosque, and several brick buildings also had been been laid to waste. Even the long, rusting casings of two US missiles sent crashing into the base in 1998 after terrorists struck two US Embassies in Africa were still present. But there were no signs of human casualties.
Local nomads, with camels laden with electronics goods and oil, traipse warily through the mountains as a B-52 loops ominously over the ravaged base. They describe the latest "escape" of Al Qaeda members from the Zawar Kili camp. "All the Arabs are down in Pakistan now," says Nik Sawat, a blue-eyed nomad, who says he was hurrying to get out of the mountain pass before the US bombers struck again. "I saw hundreds crossing the border a few weeks ago, but nothing recently. Some went to Pakistan, and some went south - their way was paved with money."
Commander Wafadar nods in agreement. But he also provides a detailed account of several suspected hideouts that Al Qaeda and Taliban members are still using inside Afghanistan.
He, like other local leaders, protests the US "go it alone" strategy. "With local cooperation, everything is possible," Wafadar claims. "Al Qaeda is hiding in the mountains and trying to blend in. The problem here is that the US bombing raids have sometimes killed just one or two Al Qaeda members along with 40 civilians."
The Afghan commander - famed for winning a battle against the Soviets in which both sides ran out of ammunition and had to fight to the death with knives - says that his men need more guns and money. He claims he's ready to begin a major "Al Qaeda cleansing" operation in the mountains of Khost and Paktia Provinces if he obtains the assistance.