Favorite Dungeons

[GAAD]

So my adventuring group had an interesting dungeon: A coral reef made out of human organs arranged into the shape of a candyland (with an illusion over all of it to make it look like actual candy) populated by skeletons covered in gingerbread who behaved like Weeping Angels.

It got me to thinking, what cool dungeons have the rest of the playgrounders made/experienced? Feel free to share!