Military Grave Search: This is the link to the German Non-Profit group that maintains all German Military Graves around the world. The German Government only donates a 1/3 of their operating budget, and doesn’t maintain graves. I could go on about the lack of concern on that idea, but typical.
In Germany you are hard pressed to find any old graves in city cemeteries. Most graves are only kept for 25 years Max (10 years in Switzerland). I was lucky to find a KIA relatives grave in the small town of Ettenhiem which had a walk of honor for WW1 and WW2 fallen.
This database is very good. Please try it if you know some fallen German relatives from WW1 or WW2. The database listed the Cemetery and location where Johan was buried.