Wrong. No American would ever say that. I am not sure if there is even a good explanation for it but there are some American cities that must be said "city of X" and others which can also be said "X city".
For example, nobody would ever say San Diego city or Las Vegas city. However, some US cities have city as part of their name such as Dodge City or New York City or Baltimore City although it is usually called only Baltimore because Baltimore City is exclusively just the inner part of the city and Baltimore has outgrown that part. Los Angeles is officially the City of Los Angeles but the larger Los Angeles area is just called Los Angeles and in common use includes areas that are actually other cities officially. For example, Santa Monica would be in common parlance part of Los Angeles but is actually its own city and is definitely not part of the City of Los Angeles but is what people would think of as being part of the city of Los Angeles. Nobody would say Los Angeles city. These conventions are learned naturally by Americans and won't be intuitive to outsiders.
Okay, I get it: You don't add the genitive -(t)i on the possessed element, don't you? So it would be "أَنا مِن مَدينة سافانا." "أَنا مِن مَدينتي مزدحمة." Obviously you don't write the genitive madinati like that, but generally, I'm correct, right? The min-preposition requires genitive -(t)i on "city" when it is not a possessive as in "from a crowded city" but you don't use it in possessive construction such as "from the city of..."?!
Next question would be: What if you want to say "I am from the city of gold that lies..." - would "gold" (ذهب dhahab) have the genitive -i marking because of min/from? I.e. does the possessor take case marking?
To respond to your other comment, I see the confusion now on both our parts. The bit you linked was not dwelled on much in my Arabic classes because, at least in my professors' views, it is not often pronounced and not often written. Grammatical harakat aren't paid much attention except for genders unless you want to talk like a legal document. They're also used for verb tenses, but one thing a time.
Thank you for taking the time to answer, Connor, but I don't think you understand my question. I know that -i means "my" in some contexts, but it also signals genitive (kasrah, see https://en.wikipedia.org/wiki/Arabic_nouns_and_adjectives#Genitive_case). I have questions about the latter use.
Because you cannot translate word for word when it comes to articles of meaning. In Arabic, the phrase counts as a definite construction so 'the' becomes redundant. Think of it this way:
"I am from a city" - indefinite "I am from the city" - indefinite, the hearer assumes you are referring to a city that was referred earlier "I am from the city of Savannah" - correct English, but kinda redundant to use 'the', because there is only one city of Savannah
"I am from city of Savannah" - this is the Arabic form, it is already definite.
So I can ask the same question right back at you from an Arabic frame of reference. Why is there a 'the' when it is not needed?
@FiX: Many thanks for the explanation. But you can understand a learner's confusion when we've been trying to remember to use the "al" prefix for "the". Also, the tips in the Geography 1 lesson with the heading "Welcome to (the) Cairo!" told us that some place names have to be proceeded by "the". So when we wonder why there is a "the" there when it's certainly not needed, it's a bit confusing to find cases where we would use "the" in English whilst it's not needed in the Arabic. So the lesson I've really learned is the first sentence in your post, thanks!
I omitted "the city of" intentionally because it is cumbersome & un-idiomatic. If someone asked me, "where am I from?" I would say, "Chicago," not, "the city of Chicago". I would probably say that even if my city were as small as Wukeegan--but I might add, "in Illinois, you know". You constantly force on me the choice between what I consider an good or intelligent translation, and your nasty bell. I tend to first indulge myself, and then get annoyed at your bell—caught between a rock and a hard place.
I omitted "the city of" intentionally because it is cumbersome & un-idiomatic. If someone asked me, "where am I from?" I would say, "Chicago," not, "the city of Chicago". I would probably say that even if my city were as small as Wukeegan--but I might add, "in Illinois, you know". You constantly force on me the choice between what I consider a good or intelligent translation, and your nasty bell. I tend to first indulge myself, and then get annoyed at your bell—caught between a rock and a hard place.