Divided between government and rebel halves for nearly two years, the historical Syrian city of Aleppo has suffered devastation on a massive scale. As the first Western journalist to reach the government-held part by road from Damascus, the BBC's Jeremy Bowen reports on how west Aleppo's civilians are struggling to survive.
Hasan Sarkhosh has responsibilities now, which is hard for a 10-year-old with bad war wounds.
He was hurt when a mortar from rebel positions hit his family's home on 17 April this year. He lives around the corner from the ruins of his old home, on a street on the western side of the city that is controlled by the government.
The boy pulled up his shirt to show what had happened to him. A wound on his back still has not healed. A heavy scar runs down the front of his stomach through his belly button. Shrapnel wounds on his neck left more scars.
Hasan and his sisters are cared for with obvious love by their grandmother and other relatives. But he tries hard to help his sisters, starting with five-year-old Widad, who sits with metal bars fixed into her leg to help pull together the pieces of smashed bone. Most of her kneecap has gone.
Hasan's youngest sister, Limar, who is two-and-a-half, cuddled him as he looked apprehensively at the strangers who had come to see them. Hasan, unlike the girls, looked old enough to have a clear understanding of the catastrophe that had changed their lives.
Limar was not hurt physically. But all the children saw their mother die in the attack. They are orphans, living with their grandmother, because a sniper killed their father a year ago.
To find out why the Syrian civil war is so hard to solve, and so deadly, come to Aleppo. All the reasons why are here. If anything they are sharper than elsewhere in Syria. Fighting men on both sides think they face a choice between annihilation or victory.
Before the war, Aleppo was one of Syria's wonders. It was the biggest city, the centre of industry, where the diverse sects who had settled here over millennia could live together.
Aleppo is one of the great historical crossroads of East and West. The three witches in Shakespeare's Macbeth curse a sailor, the master of the Tiger, who has travelled to Aleppo.
At Aleppo's heart is the Citadel, a castle set on a hill that was first fortified 40 centuries ago. Around it the old city was a tangle of alleys, humming with life and business and unlike so many historical cities in the world almost untouched by tourism.
Now, the Old City, a Unesco world heritage site, is where much of the fighting gets done. It's in ruins. The front line runs through it.
Many of the merchants, who sold everything from piles of yellow sultanas to silk, or cheap nylon football shirts and bars of hand made olive and laurel soap, have either fled or been killed.
The tension in Aleppo rose steadily once the uprising started in 2011. About a year later rebels seized much of eastern Aleppo and the countryside around it.
At times west Aleppo has been cut off, reliant on food and fuel supplies that were smuggled through the lines. It is still surrounded by armed rebels, with the exception of a narrow supply corridor that the Syrian army opened last winter.
The corridor runs from Homs, which is now under the control of Syrian President Bashar al-Assad's forces. It takes about five hours to follow a series of minor roads to Aleppo.
The last 30 miles (50km) or so are defended by dug-in Syrian artillery and tanks, as much of it is potentially under the guns of armed rebels.
The last three miles have been diverted to dirt tracks since rebels attacked the entrance to Aleppo in April.
Extremism 'the real enemy'
Aleppo is the key to northern Syria. That is why the rebels and the government both want it so much.
The way in is past a ruined housing estate of six- to eight-storey blocks. Shells have punched great holes in the buildings. Many have collapsed in on themselves, and the narrow alleys around them are blocked with rubble.
People still live in parts of the estate. West Aleppo is full of people, many of whom have lost their original homes because of the war. Terrible damage has also been inflicted on east Aleppo by the Syrian army's heavy weapons.
Before he took the BBC for a tour of west Aleppo, the provincial Governor, Mohammed Waheed Akad, showed off a collection of mainly homemade projectiles that he said had been fired at his building. He has had steel shutters attached to the windows of his office.
"These indiscriminate shells are launched at civilians in Aleppo," he said, with some anger. "They shout, 'God is great,' as they launch them, but God and Islam have nothing to do with this brutality."
Videos circulated on the web by rebels show them firing homemade mortars inside Aleppo. We went out in the governor's car to drive through ruined front-line districts.
The car was not armoured, but the governor wedged a large pistol into a glove box between the two front seats.
I asked him about the barrel bombs, containers full of explosives dropped from helicopters on to the rebel held part of the city. The governor denied the regime was killing Syrian civilians.
"The Syrian Arab army is targeting militants, like [Islamist al-Qaeda affiliate the] Nusra [Front] and Isis [the Islamic State in Iraq and the Levant] - and other extremist groups that came from outside Syria."
Islamist fighters of different levels of radicalism dominate the rebel side in Aleppo. In rural Aleppo, east towards Iraq, Isis territory begins.
Governor Akad said the West did not understand that Islamist extremism, not the Syrian government, was the real enemy. Islamist groups he said, had religious and social rituals and customs that "no human should have to tolerate".
"Making women wear the hijab [Islamic veil], their food habits. Everything they do dates back thousands of years. We follow moderate Islam that is only the worship of God. "
From the start of the war, President Assad has said that extremists, directed by foreign conspirators, were leading it.
Poverty and the humiliations imposed by a corrupt and authoritarian system helped create the uprising, and when the war began there was no hard evidence for his claims. But now Islamist fighters dominate the armed opposition.
Poor people queuing for water in west Aleppo blamed them for an attack on the city's water system that meant sewage was mixing with drinking water. One man filling a bucket said: "The militants blew up the pipes. They come here to sabotage the country and they cut the water on us."
Caught in the middle
The UN's World Food Programme feeds nearly 800,000 people in Aleppo on both sides of the front line and in the surrounding countryside.
In the west one kitchen, not the only one in the city, can on its own turn out 48,000 cooked meals a day.
Aleppo's Christian community tends to support the regime, fearing al-Qaeda and Isis on the other side.
As the Greek-Catholic Archbishop of Aleppo, Metropolitan Jean Jeanbart, was showing me bomb damage in his church close to the old city, another mortar hit the Armenian church next door with a great crash.
I asked him about the insistence in Western governments that President Assad must step down. The archbishop said there were two alternatives to the president.
If the government won the war, it would be a candidate from the army or the ruling Baath party. If the rebels won, it would be a jihadist from al-Qaeda or Isis. In the circumstances, the archbishop preferred President Assad.
Plenty of Syrians are caught in the middle, wanting neither the president nor the extremists, and hoping for peace without much regard for politics. But Syria is a prize, for the current leadership or the rebels of all different shades of belief.
The Syrian army has been winning more lately, across the country. But that might not last.
More violence is guaranteed. That frightens Mariam Akash and her nine children between the ages of two and 15. After her husband was killed by a sniper, Mariam moved them, in mid-winter, into a half-built house in west Aleppo. The older children work, only two are at school.
"We're just living on the edge of life," Mariam said. "We're always nervous, we're always afraid, When there are clashes I keep the children hiding and tell them to, 'Keep your heads down,' I'm always worried about them getting caught in the fighting."
For people like Mariam there is not time to debate whether it was the government's actions, or the West's inaction, that gave Islamist extremists the chances they have seized. Surviving the day is what matters.
Now Syria's neighbours can feel the war too. Bloodshed is seeping across Syria's borders, to Iraq worst of all. And without any kind of peace in sight, it is hard to see how that stops.