THE summer sun beat down on them as a young man stepped forward from the delicatessen storefront.
The smartly dressed royal couple barely noticed him, really, as there was some confusion over the route they were taking and the motorcade was in the process of backing up and turning around.
The date was June 28, 1914. It had been a stressful day in Bosnian capital of Sarajevo after that morning's bombing and the assassination attempt was very much playing on the couple's mind.
In fact, the change in route was because the man and his wife insisted on visiting those injured in the blast.
The husband took in the scene - the cars trying to turn, the sun glinting off the river, the Latin Bridge nearby and the small, young man, walking with determination up to him.
And then the 18-year-old, Gavrilo Princip, pulled out a pistol, held it up and fired. Point blank. Two shots. Two deaths.
Franz Ferdinand, the Archduke of Austria and heir presumptive to the Austro-Hungarian throne, as well as his wife Sophie, were dead, and the course of history was incontrovertibly changed.
WAR WAS INEVITABLE
In the early 1900s, a few key things were happening in Europe.
The industrial revolution was at its peak, but many countries were resource-poor. They needed things like coal, iron, rubber and oil to keep their new manufacturing industries going.
At the time, a legitimate way to do this was to build their empires, invading instead of trading, and taking control of lands where they could get these things for free.
Empire-building was therefore another key feature of the political landscape. As such, countries began increasing their military budgets - none more so than Germany which increased its defence spending between 1910 and 1914 by an incredible 79 per cent.
Part of this stemmed from a growing sense of nationalism and patriotism. People had an increasing sense of pride in their country, and leaders were keen to show that their nation was superior.
Add into this mix two main European alliances: The Triple Alliance of Germany, Austria and Italy; and the Triple Entente of Great Britain, France and Russia.
Some have argued that war was inevitable. Nations were keen to show their military might, to test their arms and to expand their empires.
But every fire needs a spark.
TWO SHOTS THAT KILLED 16 MILLION
Archduke Franz Ferdinand was the 50-year-old heir to the Austrian throne. Part of the Hapsburg dynasty, he had married for love to wife Countess Sophie Chotek, enjoyed trophy hunting (including kangaroos in Australia), and had spent most of his life in the army.
At the time of his death, he was inspector general of the Austria-Hungary armed forces.
Bosnia had been annexed by Austria-Hungary, and the Archduke and his wife went to the country to observe military manoeuvres and open the new state museum in Sarajevo.
But a growing Serbian nationalist movement meant that tensions were high.
On the morning of June 28, 1914, amid fairly poor security arrangements, the motorcade transporting the Archduke was attacked by would-be assassin Nedeljko Cabrinovic, a 20-year-old member of the secret society known as the Black Hand which had the previous night conspired to kill the Austrian leader.
He was just one of six men lining the motorcade's route, ready to attack.
Cabrinovic threw bomb, but things didn't go so well for the young Serb. To start with, his bomb bounced off the car and landed in the street. It blew under a different car, wounding around 16 people, but killing none and not injuring the Archduke.
Cabrinovic then popped a cyanide pill and jumped in the Miljacka River for good measure. But the pill was old and only made him vomit - and it hadn't rained in a while, so the river was just 13cm deep. Police dragged the man out of the water and he was beaten by the crowd before he was taken into custody.
Rattled by the morning's events, plans changed.
The Archduke and his wife decided to visit those injured in the blast instead of continuing with their planned itinerary.
But the motorcade went the wrong way, going the original route instead of the revised one. Hence their need to stop and turn around at the Latin Bridge, outside Schiller's Delicatessan where 18-year-old Gavrilo Princip was waiting with his loaded pistol.
Unknowingly, the teen from a poor, peasant family who grew up in a remote part of Bosnia, had just started World War I.
The two shots he fired from his FN Model 1910 pistol had, in reality, led to the deaths of 16 million people.
During his trial over the assassination, Princip said: "I am a Yugoslav nationalist, aiming for the unification of all Yugoslavs, and I do not care what form of state, but it must be freed from Austria."
He was jailed and died four years later in 1918 from tuberculosis, caused by poor prison conditions.
THE DEATH WHICH LED TO WAR
Now the two European alliances played their part. Until this point, they had been a theory, signatures on a piece of paper, a loose friendship. But now those friendships would be tested.
Immediately after the Archduke's death, there was shock across Europe, but no realisation of what it may lead to. People didn't really care about a dead Austrian Archduke, and went about their daily lives.
But jailing the assassin wasn't enough for Austria-Hungary. Blame began to be bandied around with Serbia quickly saying it had warned the Austrians that tensions were high after a strong surge of nationalism and an assignation attempt might happen.
In reply, Austria-Hungary produced a list of demands including arrests of all those involved in the plot and prevention of secret arms shipments.
Austria-Hungary declared war on Serbia, and called on Germany to join it.
But now the Triple Entente was obligated to also act. A secret treaty had been signed, saying that if any of the Triple Alliance mobilised their armies, Russia and France would fight.
Great Britain followed suit - along with all the countries in her empire - and within months, the death of one man, and a subsequent fight between Austria-Hungary and Serbia, had turned into a war involving the whole world.
WAR TO END ALL WARS
In all, around 16 million people died on the battlefields during WWI. That estimate can range up to 20 million. Another 23 million were wounded. It was one of the deadliest conflicts the world has ever seen.
The war that was meant to last just a few weeks, was meant to be over by Christmas, lasted four long years. The very landscape of Europe changed - geographically, physically and mentally.
Australia was a young country. Federation had only taken place 13 years earlier, and the nation's people were keen to do their bit for Mother England.
The country had a population of fewer than five million at the time. Of those, 38.7 per cent of the male population enlisted - around 420,000 men. Just over 60,000 died, 155,000 were wounded, 4000 were captured and 431,000 suffered non-battle injuries.
Australian and New Zealand Diggers made their name on the battlefield - particularly in Gallipoli, Turkey. Anzac Day has become part of the fabric of what it is to be an Aussie and every year on April 25, and again today, we remember those who have given their lives in conflicts before and since for the freedoms we now enjoy.
MORE DEATHS TO COME
War ended in 1918, with the armistice signed at 11am on November 11 - 100 years ago today.
The Treaty of Versailles, signed the following year, outlined the conditions of surrender.
Germany did not fare well.
It lost 65,000sq km of territories, and the seven million people who lived on those lands. Former colonies around the world, such as Cameroon and Rwanda, were taken by Allied states.
Germany was ordered to have an army of no more than 100,000 men in severe restrictions on its armed forces.
And the country was instructed to make "reparations" - essentially pay the Allied countries billions to cover the cost of the conflict.
The severity of the surrender led to resentment and poverty among the German people.
It played on the mind particularly of one young German soldier. A budding artist, he had fought on the French battlefields, been wounded at the Somme and receive the Iron Cross for bravery.
When the war ended, he began to voice his political beliefs, joining the German Workers' Party, which later became the National Socialist German Workers' Party. The young artist even designed the party's banner - a black swastika in a white circle on a red background.
His name was Adolf Hitler, and his experiences in the Great War, and his resentment of its aftermath directly led to another world war.
WWII, which raged from 1939 to 1945, killed 50 million people, though estimates to include deaths from war-related disease and famine raise that figure to 80 million. It accounted for the deaths of around 3 per cent of the world's population.
So in a way, when Princip stepped out from that doorway and fired his pistol, he had the blood of almost 100 million people on his hands.
Today is the 100th anniversary of the end of the "war to end all wars". At 11am we will take a minute to stop, be silent, and remember those who didn't come back. And we will remember those who did.
Every family has been touched by war. My uncle, great uncles, grandfather, cousins. Their stories are those of ordinary people whose fates were mapped out by the political stouches of kings and prime ministers - and one Bosnian peasant facing an Archduke on a street in Sarajevo.
- The First World War Centenary is the centenary of the First World War, which started on 28 July 2014 with commemorations of the outbreak of the war and have continued until 11 November 2018.
- Continue the conversation with Marion Langford on Twitter @mazlangford