Matthew Poole and continuators on Revelation 17:9

9 And here is the mind which hath wisdom . The seven heads are seven mountains on which the woman sitteth .

That is, here is that which requireth a Mind endued with Spiritual Wisdom.

The seven Heads which he saw the Beast with, signified seven Mountains or Hills upon which Rome is scituated, they were named before (see the Notes on v. 3.) They tell us now Rome is scituated in Campo Martio: Resp. Whatever it now is, certain it is, that in St. Iohn's time it was scituated upon them, and they are now within the compass of Rome.

Marginal references: Chap. 13.18.; Chap. 13.1.