You mean other than the gas chambers in Sachsenhausen, near Berlin:but when it was proven that no gassing took place in Germany they switched tack again and said they were in Poland.
Other than the photoes of smoke from Auschwitz, and pictures of pyres, and huge quantities of ash found.No smoky chimneys so they weren't cremated.
No ditches in the landscape so they weren't buried. So where the heck are they? I bet they went to flippin' Israel.
Studies into mass graves in the last few decades:
Is this enough pictures of mass graves for you?