There is something that both IKEA, a furniture store, and Hitman, THE stealth game, have in common;
Snail House & Swiss Cheese is a map design principle, made out of two parts, the Snail House and the Swiss Cheese.
The Snail House is an area that you travel through section by section, following a path, this is what IKEA does, having customers start at the entrance, and walk their way through every section to get to the end, the restaurant. Hitman Levels accomplish by letting the player explore through the entire map, following this path, while still keeping the map relatively small. The map feels large because it takes a long time to travel through the maze.
The Swiss Cheese is the shortcuts, for the IKEA shoppers who know exactly what they need and where it is, or employees who need to get somewhere quickly without having to walk through every section. Hitman also does this by including hidden doors, pipes to climb, etc.
Another thing that both Hitman and IKEA include in their layouts, is that they do not include dead ends. Every room should have atleast another exit out of it, even in cases such as the bathrooms in Hitman’s Dubai level, where the bathrooms connect into a laundry room.
This post was inspired by GMTK’s video on the subject, and an article by Zack Zwiezen (Just a forewarning, Hitman does include some mature themes.)
