You'll also often find that a regional port authority is responsible for both seaports and airports in a given region.

And while the structure of an airport terminal isn't quite the same as a set of finger quays for a port, there's a certain similarity between the two structures. Both are interfaces, designed for craft to approach closely and transfer cargos to/from the port. They're characterized by a highly crenelated boundary to allow for maximal surface area and transfer region.