Hah! I was wondering about that. Mine dropped me into what looks like a 3D modeled version of a real place, but sandboxed - there's no way to move around.

(that iframe embed is: https://www.google.com/maps/embed?pb=!4v1686332716861!6m8!1m... )

It led me down the path of reverse engineering these URLs though, so that's fun.