There are many airports where roads (and pedestrian walkways) are routed underneath taxiways, runways, etc. But are there any airports where airplane taxiways go under/over each other?
I can't imagine there would be (for many logistical and sanity reasons), but in this world of unusual design and construction paradigms, I've learned to not say that something has never been done. This could either be airports that are currently in use, or ones where they were used at one time, but are no longer active.