Gothic horror meets Dungeons & Dragons in Tracy & Laura Hickman's "Ravenloft"! The original 1983 adventure that was later expanded into an entire campaign setting/sub-dimension, "Ravenloft" (now available in PDF from D&D Classics) is one of the most complicated and deadly dungeons ever. Terrifying deathtraps, life-stealing ghosts, crawling zombies and evil witches all stand between the brave (and/or foolish) adventurers and their goal: to defeat the vampire master of the castle, Baron Strahd von Zarovich!
I never actually played this adventure as a kid, but the other kids in elementary school made up lots of stories about how dangerous it was. (They were slightly exaggerating when they told me about the room of 1,000 wights.) This long scroll-type map is a great addition to any gaming room or haunt of vampires.
Available as a ginormous 18"x36" print. ©Wizards of the Coast.