Another common-but-interesting thread.
Recommend a doom-psych-stoner movie.Well-known movies like Witchfinder General or Gummo are still welcome.
My first contribution is:

Le Frisson des vampires (1971)
Directed by Jean Rollin
I'm a pervert, I know that. Give me some naked women, a castle, grotesque scenes & a psychedelic soundtrack... it's enough to make me happy. Vote:10/10