04/08/2014 18:21 BST | Updated 04/08/2014 18:59 BST

As World War 1 Centenary Is Marked, A Return To Sarajevo Where An Assassin's Bullet Started It All (PICTURES)

Lights are dimmed across Britain tonight, to mark the centenary of the beginning of World War 1 and pay tribute to all those who fell - all 17 million of them, including soldiers and civilians.

A few weeks ago, I paid a visit to the place where it all began - not some Prussian government building, nor a battlefield in Belgium where so many were to lose their lives, but an ordinary-looking riverside avenue in Sarajevo, Franz Josef Street to be precise.

Archduke Franz Ferdinand and his wife Sophie were assassinated on a royal trip to Sarajevo in 1914

It was here in June 1914 that Austria-Hungary's Archduke Franz Ferdinand and his wife Sophie were paying a royal visit to inspect military manoeuvres and to open a new state museum.

But their trip ignited an uprising of anger from those who wanted the south-Slav provinces of Austria-Hungary to be absorbed into Yugoslavia

Appel Quay, with its glistening water and smart lamp posts, today looks like the riverside avenue of any smart European city

As Franz Ferdinand and his wife travelled along Appel Quay, their first would-be assassin of the group of six threw a grenade at their car. It bounced, landed underneath another car before going off, and succeeded in harming up to 20 people, but neither the Archduke nor his wife. However, the ambush did mean they had to rest for a while at the city's Town Hall, before they decided to visit the injured in hospital.

Schiller's Delicatessen where Gavrilo Princips was waiting to ambush the royal couple

In more bad luck for the couple, this meant a change of route, but no one told the driver, who took them back down Appel Quay, to Schiller's Delicatessen on the corner of Franz Josef Street. There, Gavrilo Princips was waiting. As the car slowed, he stood and shot twice with his pistol, fatally wounding both Franz Ferdinand and his wife.

It was particularly unlucky for Sophie. Throughout her married life, her comparatively low social standing had meant she had seldom been allowed to join her husband on trips and public outings. Their son later reported that she had gone along to Sarajevo out of fear for her husband. Franz Ferdinand, on the other hand, had agreed to the visit because it meant that Sophie could ride along with him for once. Such mutual devotion hence played a key part in their deaths.

An unusual memorial to Archduke Franz Ferdinand and his wife Duchess Sophie in the Sarajevo Museum, on the site of the delicatessen where Princips waited

The result... 25 individuals were brought to court for the crime, three men were eventually executed for their parts in the royal couple's deaths, but it didn't prevent the higher powers taking matters into their own hands. Austria-Hungary declared war against Serbia, Germany sided with Austria-Hungary, Britain and the rest of her Allies went with Serbia, and off they all went into the abyss of 4 August 1914, with its devastating, unthinkable consequences.

Looking at this street today, with its bustle of traffic, food stalls and gentle lapping river that makes it resemble many another European city, it is hard to believe that it could be the location for all those years of tragedy and bloodshed being commemorated a century later.

If it could happen here, it could happen anywhere. Lest we forget.