Revelation 17:9-11
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.