Museum of Sepulchral Culture (Kassel, Germany)

This sounds like a goth dream come true!  A museum that blends death-themed modern art with ancient coffins, tombstones, hearses, framed death notices, memorial photography, embalming equipment, mourning clothing, etc.   Here’s an article that goes into greater depth on this fascinating museum:

German Museum of Death Anything But Morbid

Thanks to Steve ORourke for the link.