I was just watching the old DTV Monter Hits special that aired back in the 80s. I noticed the Monster Mash segment has various clips from Skeleton Dance and Haunted House, but there is one clip featuring Dracula, the Wolfman and Frankenstein's monster laughing as well as a few clips of Mickey about to enter what appears to be an eerie looking castle (Dracula's maybe?).

Does anybody know what Mickey Mouse short this is?

I looked all over the Encyclopedia of Disney Animated Shorts website but have had no luck finding it.