I looked up a map of Everglades National Park courtesy of the national parks , and it looks like the Everglades encompas the entire southern tip of Florida. It appears to border both the Gulf and part of the Atlantic, and includes Florida Bay...
Here's the link. I know it's in wikipedia, but I am sure you'd find it in the National Parks Services website as well:
A couple of things to add tho. It is well-south of the Naples area, and I don't think the marshlands abut the waters of the Gulf or the Atlantic. It does look as though there is a little bit of a strip of beach between the marshlands and the ocean waters. I think there is the exception of Florida Bay tho, as mentioned above.
Hope this helps! Geography is my thing!
[Edited 2010-01-07 19:53:08 by steeler83]
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