You certainly cannot have an airport of the size of Newcastle that isn’t served by a motorway or a train station with a large chunk of its catchment being the sea or on the other side of a national park with single track roads.
Newcastle might not be your best example - it isn't served by a motorway, or a train station, has a large chunk of its catchement area in the sea and is surrounded by National Parks, moorland and single track roads. And lost it's easyJet base.