Revelation 17:9

Here is the mind that has wisdom. The seven heads are seven mountains, on which the woman sits.

Revelation 13:18

Here is wisdom: let him who has understanding, compute the number of the beast; for it is the number of a man; and its number is six hundred and sixty-six.

Revelation 17:3

And he brought me, in the spirit into the wilderness: and I saw a woman sitting upon a scarlet beast, full of slanderous names, having seven heads and ten horns.

Revelation 13:1

And I stood upon the sand of the sea, and saw a savage beast ascending out of the sea, having seven heads and ten horns; and upon its horns were ten diadems; and on its heads were the named of defamation.

Revelation 17:7

And the angel said to me, Why do you wonder? I will tell you the secret of the woman, and of the beast which carries her, which has the seven heads and the ten horns.

Revelation 17:18

And the woman which you saw, is the great city, that rules over the kings of the earth.

Treasury of Scripture Knowledge

Summary

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

Bible References

Here

Revelation 13:18
Here is wisdom: let him who has understanding, compute the number of the beast; for it is the number of a man; and its number is six hundred and sixty-six.

The seven

Revelation 17:3
And he brought me, in the spirit into the wilderness: and I saw a woman sitting upon a scarlet beast, full of slanderous names, having seven heads and ten horns.
Revelation 13:1
And I stood upon the sand of the sea, and saw a savage beast ascending out of the sea, having seven heads and ten horns; and upon its horns were ten diadems; and on its heads were the named of defamation.