Revelation 17:9-12
17:9 (This requires a mind that has wisdom.) The seven heads are seven mountains the woman sits on. They are also seven kings:
17:10 five have fallen; one is, and the other has not yet come, but whenever he does come, he must remain for only a brief time.
17:11 The beast that was, and is not, is himself an eighth king and yet is one of the seven, and is going to destruction.
17:12 The ten horns that you saw are ten kings who have not yet received a kingdom, but will receive ruling authority as kings with the beast for one hour.