Germany declared war on France on this day in 1914, marking France’s entry into the Great War.
President Hollande will be at Hartmannswillerkopf Mountain in Alsace today, then part of Germany and now part of France.
The almost 1,000-meter-high Hartmannswillerkopf Mountain provides a view of the Rhine Valley and was seen as a strategically important position by both the French and the Germans.
Between 20 and 30 thousand French and German soldiers lost their lives in fierce trench battles on this rocky ridge throughout 1915.
President Hollande will be accompanied by German president Joachim Gauck.
For the commemoration, both presidents will lay the foundation for a French-German museum.
They will also visit the graveyard of fallen French soldiers. Almost 1,300 Christian crosses and a white Muslim headstone mark their deaths.
A German-French historical commission has also opened a trail with 45 commemorative plaques that dot the mountainside and indicate important battlefields.
Around 250 thousand people visit this historical site every year.