It's a rocky peak overlooking the Rhine Valley — and the last resting place for more than 1,200 soldiers buried in the military cemetery and some 12,000 unidentified soldiers in the crypt.

On Friday, French President Emmanuel Macron and his German counterpart Frank-Walter Steinmeier will inaugurate a museum on the Hartmannswillerkopf peak, where German and French soldiers faced off for years during World War I.

The mount, at an altitude of 956 meters (3,136 feet) in eastern France near the border with Germany, was considered strategically important because it offered a commanding view of its surroundings.

The exact number of dead is unknown but estimates are that about 25,000 soldiers from both sides died in the fighting there. Most of them perished between January 1915 and January 1916, when the two sides successively tried to capture and re-capture the peak, using shells, poison gas and flamethrowers. It was known to soldiers as the mountain that "devoured men".

After that, the front line that ran across the peak remained relatively stable until the end of the war in 1918.

Hartmannswillerkopf has become a symbol that former enemies France and Germany have now put aside their differences to pave the way for peace. A national monument, surrounded by forests, now commemorates the bloody battle.

At the site, visitors can see trenches and bunkers built by soldiers and what remains of a German cable car used to bring food and equipment up the mount.