MLT's answer is correct. The second sentence in your question is: I went to 'the' National Bird Park? If I know where the National Bird Park is located (i.e. you told me where you went), then you could say "I went to the National Bird Park (the park that is located at or near the place where I said I went)." If I don't know where you went, then you must say "I went to a national bird park."

Thanks, Richard! I didn't see the second question. :)

No, "the" (definite article) is unnecessary to use here. Because "Fort Napoleon" is a proper noun (titles, places, names, etc.), it is specific without a definite article. (Unless, of course, "The" was a part of the location's name...then "the" should be included.) Both of the following are correct (notice that when "fort" is not a specific name of a place, you SHOULD include "the.") 1. I went to Fort Napoleon. 2. I went to the fort.