It is a war signposted with numbers so huge they are hard to comprehend.
More than 11 million Syrians have fled their homes — nearly half the population of Australia.
Observers estimate more than 320,000 have been killed — almost the population of Canberra.
The United Nations says 2016 was the deadliest year yet for children in Syria and estimates nearly 6 million children are in need — more than one-and-a-half times the number of school students in Australia.
And, the United Nations says, about 280,000 are living under siege.
For some children, it is a war older than them.
And it is a war sparked by the graffiti of a child at the time.
One Wednesday evening early in the Arab Spring, 14-year-old Naief Abazid and his friends scrawled a message on a wall aimed at President Bashar al-Assad: “Your turn is coming, Dr.”
Their message — and their subsequent detention and torture — gave rise to rebellion.
The rebellion was met by automatic weapons.
It was a popular uprising that has become a proxy war, the battlefields filled with a multitude of flags as guns were turned on each other.
Rebels fighting Syrian forces, Syrian forces fighting rebels.
Russia bombing rebels, Russia bombing fighters from the self-proclaimed Islamic State.
Kurds fighting Syrian forces, Turkey fighting Kurds.
IS fighting everyone.
In this fractured war, IS has provided a common enemy.
The ancient city of Palmyra was wrested from its grasp in March last year — a symbolic win — only to be lost and then won again over the course of the year.
It showed the transient nature of victory in this war.
Now, United States Marines have joined the fighters on the ground, deployed by new US president Donald Trump.
Middle East analyst Rodger Shanahan, at the Sydney-based Lowy Institute, says the new US administration is still grappling with its understanding of the protracted conflict.
“But I think they’re now coming to grips with the complexity of the Syrian situation, as the Obama administration has had to do for the six years before, so I think, while he has said a number of things about how simple it would be to defeat Islamic State in Syria, that’s only ever been one side of the question.”
In the last year, some factions have won ground, some have lost.
Military commanders say IS is on the defensive now.
But this was the year the world watched a battle for a city.
A year ago, Aleppo was in its 44th month of siege, with bombs raining down from Russian and Syrian warplanes on more than 300,000 people in the city’s rebel-held east.
Four of those bombs hit Al Quds hospital in April, killing Dr Muhammad Wassim Maaz, one of the city’s last paediatricians.
A month later, an aid convoy bound for eastern Aleppo was bombed, killing 14 aid workers.
The United Nations now says it was a deliberate act by the Syrian government, a war crime.
In New York, then UN secretary-general Ban Ki-moon was incredulous.
“Just when we think it … it can’t get any worse, the bar of depravity sinks lower.”
Three days later, Syrian forces declared an offensive to capture eastern Aleppo.
In the weeks and months that followed, so-called White Helmet volunteers reported the use of chemical weapons — toxic chlorine-gas attacks — across the city.
By December, the rebel-held east was mostly in government hands, the evacuation of civilians and rebels beginning after numerous delays.
By December 22, pro-government forces were celebrating victory.
Rodger Shanahan says it has changed the narrative of the war.
“We’ve probably seen the shift of the momentum go towards the Assad regime somewhat. But they’re still not in any position to reassert control over large parts of Syria that remain outside of their control.”
Medecins Sans Frontieres’ Evita Mouawad spoke to SBS from the organisation’s regional headquarters in Amman.
“The high insecurity inside Syria and the constantly shifting front line has made it very difficult for us to access all these areas on a regular basis. We are still unable to access government-held areas. And we have repeatedly asked the Syrian government to access these areas since 2012, however we have always been denied.”
She says some of people’s most basic needs have been ignored.
“Emergency care has been prioritised over the last years, and this is why non-communicable diseases and mental health and vaccinations have maybe not been prioritised. But, of course, if you have heart disease or diabetes and it’s not treated for a long period of time, you could also … also die.”
In Syria, even water has become a weapon, with access to springs and pumping stations considered a strategic gain.
Deep frustration has set in on all sides after numerous rounds of peace talks, numerous ceasefire violations.
Discussions over the last year have moved from those brokered by the United Nations in New York and Geneva to those led by Russia and Turkey in Moscow and elsewhere.
Syria’s opposition says it will not be attending this week’s negotiations in Astana.
Mr Shanahan says any progress is likely to be slow.
“Sides who are backing the Assad regime have more skin in the game than those who are backing the opposition, and I think, if we’re talking about an issue of exhaustion, I think regional backers are going to be exhausted before Russia and Iran and the Syrian government are. How that plays out and how long that takes, nobody really knows.”
But even in this war, so entrenched, so complex and now entering its seventh year, Evita Mouawad says those living through it still believe an end will come.
“We see hope in the faces of the people that we meet every day. We see hope, you know, in women and children who have travelled such a long way in search of safety and in search of better lives. So, they really give us hope, because they’re very resilient and they want to believe that, one day, they’ll be able to go back to their homes and just live normal lives like everybody else.”