I personally think the pound is the saddest place for many cats and dogs.
I hear that Auschwitz is terribly sad - the atmosphere is just deep sadness.
Personally, the saddest place I've been to was a German war cemetery in northern France. Thousands of black volcanic rock graves, and almost all of them with the name of a soldier barely older than a boy - 15, 16, 17, 18 years old.
Ratville is not the happiest place; it's the saddest because when people finish their time there they're broke and all they have had is sensation, and probably bought a lot of crap that will wind up in the trash or a landfill.
Not the pound, some animals in the pound get adopted, I think the saddest place on earth is the WWII memorial museum in Israel.
The saddest place I've been was Dachau concentration camp, but any of the concentration camps would probably have had the same effect.
In the USA that would be the old coal mining town in the southern part of West Virginia. Elsewhere in the world, that would be the ghettos of the big cities in Africa. Even worse that the impoverished villages of Russia.
I think Palestine is the saddest place
Pripyat Ukraine.
the rohingya people in mayanmar are also the saddest races in the world, i hope everyone of us live fair the same...we human live and guarantee visa on this planet for 100 yrs. the rest judgement will follow, hell or heaven.......
Syria
Siberia