Bet you didn't know that graves in Germany are recycled??
I read about this in an article in Der Ahnenforscher, the monthly newsletter of the German Genealogy Group (based in Long Island, NY; Google it). James Derheim wrote that if you're planning a research trip to Germany and you want to visit your ancestors' graves, you will most likely be very disappointed. "With 83 million people living above ground in Germany, a country the size of Wisconsin, there isn't much room leftover for new burial plots. The outlines and dimensions of a cemetery are usually constant, kept the same as they have been for hundreds of years."
So what do Germans (and other Europeans) do? After a period of about 15-20 years, if the family no longer pays for the upkeep and "rental" of the burial plot, the remains of the person buried there are removed, the headstone taken away and a new person buried in that spot.