WW1 War Grave and Locket

While searching for my grandfather's WW2 Home Guard service certificate which I haven't found yet, I found a couple of old photos, one of which I have been looking for, on and off, for at least 25 years.

When my grandmother passed away 25 years ago she left me the gold locket, pictured, which originally contained a small photo of a distant relative killed in WW1. He died of his injuries, received in action, in captivity, as a prisoner of war in 1915, aged 20. The soldier's mother or sister had the gold locket with his photo in it and because he was a relative of my gran, it eventually came to her. I always thought it foolish that my gran had the soldier's photo replaced with her own photo and my grandfather's photo. Fortunately, my gran saved the soldier's photo, stuck to a piece of card and as it later turned out the completely wrong details on how he lost his life, written on the back. I last saw the photo of the soldier in the late 1980's, a long time before my gran passed away.

After the end of WW1 the parents did visit the grave, taking the photo of the grave, as I understand it in the 1920's. It is close to the Belgium border just inside France on ground that was held by the Germans for much of WW1. What is interesting, from looking at the 1920's photo of the grave, is that it is looking as if the cemetery is starting to get overgrown, as early as the 1920's, and not the meticulously kept places that they are today.