There is a garage in the elektro docks area (hard to miss + pic included) that is raised up quite high. You can vault into it and walk through the walls from one to the next and are actually in the floor which, in that area, is pretty exploitable. Vaulting in is the only way in - its raised too high to just walk in - which is how I figured this out and how I imagine several others will end up finding out as well. {F32816}