Another name for a multi-level interchange where high-speed flyovers cross over one another or another bridge. These ramps may have one or more lanes, and the flyovers may rise over each other to an impressive height. Stack interchanges are generally found in where freeways were built later in less developed areas, where ample right of way was available. California, Arizona and Texas are home to numerous stack interchanges. See Kurumi’s Stack Interchanges for more.