ɹˈeɪlweɪ stˈeɪʃənz sᵻlˈɛktᵻd fɚðɪ ˌoʊvɚɡɹˈaʊnd nˈɛtwɜːk wɜː ðoʊz wɪð ɐ sˈɜːvɪs fɹˈiːkwənsi ʌv fˈoːɹ ɔːɹ mˈoːɹ tɹˈeɪnz pɜːɹ ˈaʊɚ tʊ ɐ lˈʌndən tˈɜːmɪnəs.
Railway stations selected for the Overground Network were those with a service frequency of 4 or more trains per hour to a London terminus.