ORADOUR-SUR-GLANE, France -- When President Barack Obama joins other heads of state Friday in France to mark the 70th anniversary of D-Day, attention will focus on the Allied offensive's main landing site, the beaches of Normandy.
But on a continent that saw a generation slaughtered in combat and millions more perish in the Nazi concentration camps in Germany and Poland, there are many other poignant reminders of World War II.
In this small town in the Limousin region more than 300 miles south of Omaha Beach, people will gather to remember the worst Nazi atrocity on French soil.
Although what happened didn't change the course of the war like the Allies' arrival at Normandy, it's important for how the war is remembered today.
Three days after D-Day, on June 9, 1944, an armed Waffen SS infantry unit from Adolf Hitler's brutal Das Reich regiment rounded up this town's entire population in an act of revenge for the alleged kidnapping of a Nazi commander by the French Resistance. The men were massacred with machine guns before their bodies, some still alive, were covered in hay and incinerated. Women and children who sought refuge in the church were locked in, and the building set alight. Of 500 people inside, only one child survived.
A few escaped the bloodshed by lying under corpses or in nearby fields. Some others returned from work in nearby towns and villages that evening to find their homes decimated, their family and friends burned to ash. The Germans torched the town so thoroughly that no building escaped the flames.
In all, 642 people died that day, including 193 children, their bodies mostly unidentifiable. The event would come to horrify the country.
The following March, when Charles de Gaulle, by then the interim French government's leader, arrived to pay his respects, he was so horrified by what had happened that he ordered the village abandoned.
Charred cars were left on street corners and in burned-out garages; sewing machines and bicycles remained exposed to the elements. The railway tracks would remain idle.
De Gaulle wanted Oradour-sur-Glane to serve as a reminder to future generations of what human beings can do to each other under the most appalling of circumstances. The extraordinary loss of life in what was once a very ordinary French town would be a symbol of everything wrong with war.
In the years that followed, a new town was built across the road from the old one. It now provides car parking, cafes and accommodation for tourists who come here, largely on word-of-mouth recommendations, to visit what's now a ghost town.
More than 130,000 people come to Oradour-sur-Glane each year to wander the abandoned streets, mostly in silence. Last September, the presidents of Germany and France visited the village to join hands with survivor Robert Hebras, then 88.
In January, German prosecutors charged an 88-year-old ex-soldier in connection with the massacre, one of six people to have been accused after Germany reopened a war crimes case into the attack in 2010.
Elsewhere in France, hundreds of thousands more people visit the beaches of Normandy and poppy fields of the Somme, where one of the deadliest battles of World War I occurred.
Despite its somber subject, war tourism is big business, contributing millions of dollars to the French economy each year. This year is expected to be more lucrative than ever, with an expected 60 percent increase in visitors.
In the Calvados department of Lower Normandy alone -- where most D-Day ceremonies take place -- commemorative tourism generates an estimated $280 million a year. At last count, there were 64 hotels and 860 bed-and-breakfasts and self-catering holiday homes -- or gites -- within reach of the landing beaches.
As excitement over the 70th anniversary started building last year, Americans represented almost 40 percent of foreign tourists -- or more than 19 percent of all tourists -- in the vicinity.
But reminders of the war are everywhere in France. Every village, town and city lived under the Nazi shadow, and every single one has a memorial to its dead.
Elsewhere across Europe, the list of places that witnessed unspeakable horrors and are now open to the public is long, from the former World War II concentration camps of Auschwitz, Dachau and Bergen-Belsen, to the Belgian town of Ypres, all but annihilated during World War I but now home to an extraordinary museum.
Those places are still doing what De Gaulle hoped: Their ghosts are still alive, reminding the world about the horrors that war continues to inflict on innocent people everywhere.