WWI mine crater

This is a private photo from my collection. It was taken in 1924, by me, just kidding. It says: “Hill 108”, mine crater near Reims (Rheims). May anyone tell me about this “mine”?

This is a photo of a crater from a mine explosion - not from a land mine but resulting from a system where one side tunneled a mine shaft underground towards and under the enemy defenses. The mine was then packed with an enormous amount of explosives and then detonated.
They were not uncommon during WW1.
Here in the U.S. you can visit the remains of the mine explosion from 1864 outside Petersburg, Va. After the explosion troops from both sides rushed into what is known as the battle of the Crater.

Exactly; sappers from either side would tunnel towards enemy lines, lay a huge charge. fire it at a predetermined time, and an attack would be launched to try to capture the far edge of the crater while the defenders were still trying to figure out what happened. Reims was close to the front lines for most of the fighting during WW1, and either side could have blown this particular mine, but it probably dates from heavy fighting in 1916, concurrent with the Somme offensive.

The biggest one still visible is the Lochnagar Crater about a half a mile east of the villiage of La Boisselle on the Somme Battlefield.

It was blown at zero hour on the first day of the Somme. You can probably google up some images but I haven’t got time to look now.