Is it correct to say - a historical site
- an historical site
- an hispanic
- a hispanic
There is no uniform consensus on this issue. People who speak a dialect of English where the h sound is silent at the beginning of a word find it natural to use the word an in both spoken and written English. Since this particular dialect fature is present in all social classes, it is not judged to be substandard. Write it the way you say it, just be consistent.