Jack Kirby was involved in a number of odd projects in his life, especially in the eighties when he was more or less out of conventional comic books. One was a motion picture proposal called The Lord of Light, based on Roger Zelazny's book of the same name. For it, he did a pile of concept sketches as well as some designs for a proposed theme park related to the proposed movie. Above is one drawing of what the theme park might have looked like. (The odd part is that as wild and untethered to reality as Jack's imagination was, it might have been fairly simple to build buildings that looked like his did. His world had balance and mass and structure.)
The film never got made but it was apparently helpful in the freeing of six Americans who were trapped in Iran. This article tells the whole bizarre story.