I think that Ken is talking about the "real" Castellion "airport". It's located by the sea, in El Grao de Castellon. A small rwy used by small airplanes and Ultralights.
A very nice place to stop over and have a great paella.
Yes I am, this small airfield has a great history being built in the Spanish Civil War.
It is right on the coast with a road seperating it from the beach. Greedy developers have built arround it and when I was there last month is was looking rather sad.
Nice tarmac strip, now has a few private a/c local Helivac and ag-planes, plus the Royal Valencia Flying Club.
Check it out it the people are great aviators.