Finding the list of cities in Mindanao online was not easy as I thought it would be. I had to confirm each of the city compiled in this Wikipedia link.
I found a cities of Mindanao list in this website, it has only 27 cities, it was not updated. So, I had to make my own list.
This tally of mine has 29 Mindanao cities, and this is useful for travelers, or for students for their research.
Cagayan de Oro