Here is a learning support on using a comma in a location address. This is the tenth of a series of fifteen such documents, all from the same punctuation manual, therefore all intra-connected, posted here. (You can find an excursus on this choice of publishing practice here.)
If you find typos in this document, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.