Subscribe to The Chicago Manual of Style Online
Q. An index I’m editing has the entry “The Dalles, OR.” Would it be correct to change the entry to “Dalles, The, OR”? Or would it be less awkward to leave that as “The Dalles, OR”?
A. Index “The Dalles” under “Dalles, The, OR,” on the principle that most readers will know not to look for a term under an article, whether definite (the) or indefinite (a, an).
CMOS users: Don’t forget about search. Even those of you who are using the printed book and don’t have a subscription to CMOS Online can benefit from it. For example, if you enter “The Dalles” or “Dalles” (that’s an es, not an as!) in the search box, you’ll be directed to paragraph 16.91, which answers the question above.