How to change city to city distance?

I just started playing CiV again to see if it has gotten much better with the latest patches, and I got a start a few tiles away from the coast. I tried to settle a city on the coast but found I could not settle a city within four tiles of another city! I think this is a bit ridiculous and I would like to change it, but I'm not sure what file to look in. Is it in the xml or python (does CiV use python)? What file is it?

--Thanks,
Gary

IIRC it's "MIN_CITY_RANGE" (in GlobalDefines.xml).