What airport has this walkway over a taxiway?
This image was taken at London Gatwick. The bridge connects two portions of the North Terminal, right next to where the North Terminal is labeled on this map:



London Gatwick claims to be the first airport to have such a feature. As can be seen in the photo, it is the largest in the world, high enough for a 747 to pass underneath.

This is not the only airport to have such a feature, though. Denver International also has a bridge (picture) over the taxiway connecting the terminal building with Concourse A. This one is not as high as the bridge at Gatwick and can't clear anything larger than a 737.