The verse is speaking about the temple mount. Also known as Mount Moriah.
The beast-king will have his end there in Daniel 11:45
Daniel 11:45 And he shall plant the tabernacles of his palace between the seas in the glorious holy mountain; yet he shall come to his end, and none shall help him.
Let's look at this from another perspective. This discussion about mountains started from what it says in this verse:
Revelation 17:9 And here is the mind which hath wisdom.
The seven heads are seven mountains, on which the woman sitteth.
Tell me, why would it take any wisdom to understand that the seven mountains are literal mountains? That would be a no brainer and take no wisdom at all if that's what it was saying. But, it says the woman sits on those seven mountains. What else does the woman sit on? Literal, physical things or symbolic things?
Revelation 17:1 And there came one of the seven angels which had the seven vials, and talked with me, saying unto me, Come hither; I will shew unto thee the judgment of
the great harlot that sitteth upon many waters: 2 With whom the kings of the earth have committed fornication, and the inhabitants of the earth have been made drunk with the wine of her fornication. 3 So he carried me away in the spirit into the wilderness: and
I saw a woman sit upon a scarlet coloured beast, full of names of blasphemy, having seven heads and ten horns.
So, in addition to the seven mountains, the woman also sits on "many waters" and "a scarlet coloured beast, full of names of blasphemy, having seven heads and ten horns".
Revelation 17:15 And he saith unto me,
The waters which thou sawest, where the harlot sitteth, are peoples, and multitudes, and nations, and tongues.
The many waters the woman sits on are not literal waters, but rather "peoples, and multitudes, and nations, and tongues". No matter what anyone thinks the scarlet colored beast that the woman sits on represents, it's not a literal beast with seven heads and ten horns.
So, tell me how the symbolic woman, who sits on symbolic waters and a symbolic beast, sits on literal, physical mountains rather than symbolic mountains? Where is the consistency in that?