Solstice is a little-known game that was released in 1990 on the NES. It is a non-linear platform/puzzle/adventure game with an isometric perspective. To give it some credit, it's one of the finest games in its genre and the genre itself inspired games like Super Mario RPG.
Being a maze, a map of Solstice is very helpful. Although, part of the fun comes from discovering the layout by oneself so I would definitely recommend trying the game before looking at the map. Or at least watch the kick-ass intro.
Back then, players were expected to draw their own maps on graph-paper. Some gaming magazines published crude maps as well. However, what's better than having a photographic map that also shows the actual content of the rooms?
And it took 22 years after the release of the game for someone to finally succeed in making a seamless photographic map of Solstice. Why? Because the rooms only fit together in 2D on graph-paper. The game creators didn't keep track of room altitude across multiple rooms. That makes the in-game space physically impossible across groups of looping rooms.
The solution was to make every impossible loop an optical illusion à la Penrose stairs. Thus, by carefully placing these optical illusions everywhere, it was possible to illustrate the map as an “exploded-view drawing” that looks possible. It's a technical feat that took about 250 hours of work.
In fact, it won the December 2014 "Map of the Month" on VGMaps.com.
"Solstice" is a trademark of Software Creations Ltd. ©1989
This map only serves as a nonprofit technical demonstration. The full disclaimer is at the bottom right corner of the image.