Libya's Western Mountains - the 'forgotten war'
The Western Mountains are almost the "forgotten front" in the complex war raging across Libya - and it is a violent front.
Shortly after arriving in the town of Nalut, an hour's drive from the Tunisian border, I heard a series of terrifying explosions.
A volley of Grad missiles - self-propelled explosive rockets about a metre long - had torn into buildings and smashed into the rocky outcrops that surround Nalut.
They were fired by troops loyal to Col Muammar Gaddafi from their positions in the valleys and plains below the Western Mountains, or Jebel Nafusa.
On this occasion, no-one was reported hurt.
But the basic hospitals of the mountains - and the more sophisticated medical facilities of neighbouring Tunisia - are full of hundreds of injured from the forgotten front.
The day before I arrived in Nalut I heard Nato planes circling the area.
I later learnt that these Nato planes had attacked a pro-Gaddafi position in Ain Ghezaia, just below the mountain road leading to Nalut.
"We are very pleased with this Nato attack. It has reduced the number of Grad attacks," one resident of Nalut said.
But - as I discovered - it has not stopped them.
'Painfully young men'
Since April, the mainly ethnic Berber rebels have consolidated their hold on a string of towns from the Tunisian border in the far west to within a few hours' drive of Tripoli.
But the final drive to the capital - if it comes - will be a fierce battle.
The general picture in the Western Mountains is that the rebels hold the high ground, while Col Gaddafi's troops hold the heavy weapons.
Most of the Berber rebels, in a loose alliance with the National Transitional Council in Libya's second city, Benghazi, have only small arms - rifles or hand-held machine guns.
Some have larger guns mounted on the back of pickups, known as "technicals" after their widespread use in Somalia, but these are rare.
The rebels count instead on their superior knowledge of the mountains against Col Gaddafi, in much the same way that Libyan nationalists battled the colonial power, Italy, by taking to the high ground.
In other battles, the rebels have few advantages against the arsenal of heavy weapons and tanks that Col Gaddafi can deploy.
"We rely on our courage - and on Nato," said another man.
I watched a group of rebels training in a barracks in Nalut.
They were keen and roused their morale with constant shouts of "Allahu Akhbar" or renditions of the old Libyan national anthem which Col Gaddafi banned.
But they were painfully young men who did not look ready for war.
The soldier who fired a gun into the air to encourage them as they scrambled under barbed wire on the training ground needed help with reloading it.
To be fair, these were mostly new recruits.
Rebels in other parts of the mountains are said to be far better trained.
Those who have seen them operate say they are fearless and totally committed to their cause.
'Jigsaw of war'
Like elsewhere in Libya, they want the overthrow of Col Gaddafi, less corruption and better social services like education and health.
But here in the Western Mountains there is also another motive - the reassertion of the ancient Berber culture that Col Gaddafi tried to suppress.
For now, Nalut is a shadow of its former self.
Over the two days I spent there I did not see a single woman or small child.
They have almost all taken refuge in neighbouring Tunisia or in other Berber towns in the mountains.
Before the anti-Gaddafi uprising began in earnest in Nalut, in April, the town had a population of about 30,000.
Now it has less than 8,000 - almost all men of fighting age.
I asked a senior rebel commander in the Western Mountains - which dip towards the sea near Tripoli - whether their strategy was to continue the march on the capital.
The commander, who asked not to be named because he had family in Tripoli, replied: "Maybe, but I can't fight on towards Tripoli when I also have the enemy at my back."
He was referring to the Sahara Desert town of Ghadames on Libya's south-western border with Algeria.
There have long been suspicions that while Tunisia, following the overthrow of President Zine al-Abidine Ben Ali, backs the rebels, the Algerian army may prefer Col Gaddafi staying in power in Libya.
It is another piece in Libya's complex jigsaw of war.
Just as some of the Arab tribes and the ethnic Berbers may have motives that transcend the generalized "revolution", regional powers have their own agendas too.
I asked the commander if he thought Algeria was supplying Col Gaddafi with weapons.
"He has plenty of his own," the senior rebel replied.
"I don't know if the Algerian government is involved," he said, enigmatically, "but maybe it is."