Revelation 17:9

Here is a mind having wisdom. The seven heads are seven mountains, where the woman sits upon them,

Revelation 13:18

Here is wisdom. Let the one having understanding count the number of the beast: for it is the number of a man. And his is, Six hundred and sixty-six.

Revelation 17:3

And he carried me away in the Spirit into the wilderness. And I saw a woman sitting on a scarlet beast, having the names of blasphemy, having seven heads and ten horns.

Matthew 13:11

He responding said to them, Because it has been given unto you to know the mysteries of the kingdom of the heavens, but to them it has not been given.

Matthew 24:15

Then when you may see the abomination of desolation, spoken of by Daniel the prophet, standing in the holy place (let him that readeth know),

Revelation 13:1

And I stood upon the sand of the sea. And I saw a beast rising up out of the sea, having ten horns and seven heads; and upon his horns ten diadems, and upon his heads names of blasphemy.

Revelation 17:7

And the angel said to me, Wherefore wast thou astonished? I will tell thee the mystery of the woman and of the beast which carries her, having the seven heads and ten horns.

Revelation 17:18

And the woman whom you saw is the great city, the one having dominion 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 the one having understanding count the number of the beast: for it is the number of a man. And his is, Six hundred and sixty-six.
Matthew 13:11
He responding said to them, Because it has been given unto you to know the mysteries of the kingdom of the heavens, but to them it has not been given.
Matthew 24:15
Then when you may see the abomination of desolation, spoken of by Daniel the prophet, standing in the holy place (let him that readeth know),

The seven

Revelation 17:3
And he carried me away in the Spirit into the wilderness. And I saw a woman sitting on a scarlet beast, having the names of blasphemy, having seven heads and ten horns.
Revelation 13:1
And I stood upon the sand of the sea. And I saw a beast rising up out of the sea, having ten horns and seven heads; and upon his horns ten diadems, and upon his heads names of blasphemy.