1) The only references to great <3173> city <4172> in the Greek are in the Revelation. The first reference definitely refers to Jerusalem "where their Lord was crucified."  

Revelation 11:8 and their dead bodies will lie in the street of the great <3173> city <4172> which is allegorically called Sodom and Egypt, where their Lord was crucified. 

Check out the others. 

Revelation 16:19 The great city was split into three parts, and the cities of the nations fell, and God remembered great Babylon, to make her drain the cup of the fury of his wrath. 

Revelation 17:18 And the woman that you saw is the great city which has dominion over the kings of the earth." 

Revelation 18:10 they will stand far off, in fear of her torment, and say, "Alas! alas! thou great city, thou mighty city, Babylon! In one hour has thy judgment come." 16 "Alas, alas, for the great city that was clothed in fine linen, in purple and scarlet, bedecked with gold, with jewels, and with pearls! 18 and cried out as they saw the smoke of her burning, "What city was like the great city?" 19 And they threw dust on their heads, as they wept and mourned, crying out, "Alas, alas, for the great city where all who had ships at sea grew rich by her wealth! In one hour she has been laid waste. 21 Then a mighty angel took up a stone like a great millstone and threw it into the sea, saying, "So shall Babylon the great city be thrown down with violence, and shall be found no more; 

2) Jerusalem is guilty of all of the blood of the righteous, saints, and prophets... 

Matthew 23:34 Therefore I send you prophets and wise men and scribes, some of whom you will kill and crucify, and some you will scourge in your synagogues and persecute from town to town, 35 that upon you may come ALL the righteous blood shed on earth, from the blood of innocent Abel to the blood of Zechari'ah the son of Barachi'ah [A to Z], whom you murdered between the sanctuary and the altar. 36 Truly, I say to you, all this will come upon this generation. 37 "O Jerusalem, Jerusalem, killing the prophets and stoning those who are sent to you! How often would I have gathered your children together as a hen gathers her brood under her wings, and you would not! 38 Behold, your house is forsaken and desolate. 39 For I tell you, you will not see me again, until you say, 'Blessed is he who comes in the name of the Lord.'" (see also Luke 11:49-51) 

while it is Babylon who is found drunk with the blood of the saints, prophets, and all slain upon the earth. 

Revelation 17:5 and on her forehead was written a name of mystery: "Babylon the great, mother of harlots and of earth's abominations." 6 And I saw the woman, drunk with the blood of the saints and the blood of the martyrs of Jesus. When I saw her I marveled greatly. 

Revelation 18:21 Then a mighty angel took up a stone like a great millstone and threw it into the sea, saying, "So shall Babylon the great city be thrown down with violence, and shall be found no more... 24 And in her was found the blood of prophets and of saints, and of ALL who have been slain on earth." 

Revelation 19:2 for his judgments are true and just; he has judged the great harlot who corrupted the earth with her fornication, and he has avenged on her the blood of his servants." 

3) Because of her guilt, Jesus warns Jerusalem of her house being left desolate, and tells His disciples of it's destruction. 

Matthew 23:37 "O Jerusalem, Jerusalem, killing the prophets and stoning those who are sent to you! How often would I have gathered your children together as a hen gathers her brood under her wings, and you would not! 38 Behold, your house is forsaken and desolate. Matthew 24:1 Jesus left the temple and was going away, when his disciples came to point out to him the buildings of the temple. 2 But he answered them, "You see all these, do you not? Truly, I say to you, there will not be left here one stone upon another, that will not be thrown down." 

The disciples first question to Him... WHEN will this [destruction of the temple] occur? 

Matthew 24:3 As he sat on the Mount of Olives, the disciples came to him privately, saying, "Tell us, when will this be, and what will be the sign of your coming and of the close of the age?" 

Luke 21:20 "But when you see Jerusalem surrounded by armies, then recognize that her desolation is at hand. 21 "Then let those who are in Judea flee to the mountains, and let those who are in the midst of the city depart, and let not those who are in the country enter the city; 22 because these are days of vengeance, in order that all things which are written may be fulfilled. 23 "Woe to those who are with child and to those who nurse babes in those days; for there will be great distress upon the land, and wrath to this people, 24 and they will fall by the edge of the sword, and will be led captive into all the nations; and Jerusalem will be trampled under foot by the Gentiles until the times of the Gentiles be fulfilled.  

I am continually astonished when people view Luke 21:20-24 as a past occurrence. Considering the fact that the preceeding verses as well as the following verses are nearly identical to the accounts in Matthew and Mark, and considering the fact that Dan 11:45 has the Antichrist camped out "between the seas and the beautiful Holy Mountain" around the time of the beginning of the great trib (see 12:1), and considering Rev 11:2 says the outer court of the temple is given to the nations (Gr. ethnos) who"will tread under foot the holy city for forty-two months," I think it is entirely probable that Jerusalem's desolation is yet future, and she "will be trampled under foot by the Gentiles (Gr. ethnos) until the times of the Gentiles (Gr. ethnos) be fulfilled." 

Could this desolation Jesus warns of be a part of the destruction of Mystery Babylon the Great?... initiated by the abomination of desolation? 

4) The Lord, through the prophet Jeremiah, warns "the daughter of Zion", pictured here as a harlot, and describes her desolation. 

Jere 4:27 For thus says the Lord, "The whole land shall be a desolation, Yet I will not execute a complete destruction. 28 "For this the earth shall mourn, And the heavens above be dark, Because I have spoken, I have purposed, And I will not change My mind, nor will I turn from it." 29 At the sound of the horseman and bowman every city flees; They go into the thickets and climb among the rocks; Every city is forsaken, And no man dwells in them. 30 And you, O desolate one, what will you do? Although you dress in scarlet, Although you decorate [yourself with] ornaments of gold, Although you enlarge your eyes with paint, In vain you make yourself beautiful; [Your] lovers despise you; They seek your life. 31 For I heard a cry as of a woman in labor, The anguish as of one giving birth to her first child, The cry of the daughter of Zion gasping for breath, Stretching out her hands, [saying,] "Ah, woe is me, for I faint before murderers."  

Compare this account to the description of Mystery Babylon in the Revelation. 

Reve 16:19 And the great city was split into three parts, and the cities of the nations fell. And Babylon the great was remembered before God, to give her the cup of the wine of His fierce wrath.. 17:4 And the woman was clothed in purple and scarlet, and adorned with gold and precious stones and pearls, having in her hand a gold cup full of abominations and of the unclean things of her immorality... 16 And the ten horns which you saw, and the beast, these will hate the harlot and will make her desolate and naked, and will eat her flesh and will burn her up with fire. 

Could this merely be a coincidence? 

5) Both Jerusalem and Babylon are destroyed by forces coming from the north. 

Jer 1:14 Then the Lord said to me, " Out of the north the evil will break forth on all the inhabitants of the land. 15 "For, behold, I am calling all the families of the kingdoms of the north ," declares the Lord; "and they will come, and they will set each one his throne at the entrance of the gates of Jerusalem, and against all its walls round about, and against all the cities of Judah... 7:34 "Then I will make to cease from the cities of Judah and from the streets of Jerusalem the voice of joy and the voice of gladness, the voice of the bridegroom and the voice of the bride; for the land will become a ruin... 26:2 ...'Stand in the court of the Lord's house, and speak to all the cities of Judah, who have come to worship [in] the Lord's house... 9 ...'This house will be like Shiloh , and this city will be desolate, without inhabitant' 

Jer 50:1 The word which the Lord spoke concerning Babylon, the land of the Chaldeans, through Jeremiah the prophet...3 "For a nation has come up against her out of the north ; it will make her land an object of horror, and there will be no inhabitant in it. 

6) Jerusalem and Babylon both drink from the cup of the Lord's anger. 

Isai 51:17 Rouse yourself! Rouse yourself! Arise, O Jerusalem, You who have drunk from the Lord's hand the cup of His anger; The chalice of reeling you have drained to the dregs.  

Reve 16:19 And the great city was split into three parts, and the cities of the nations fell. And Babylon the great was remembered before God, to give her the cup of the wine of His fierce wrath. 

7) One angel with a bowl said, "Come, I will show you the judgment of the great HARLOT..." (Rev 17:1-19:4.) Immediately after that (Rev 19:5...) the BRIDE is ready! Then in Rev. 21:9..., another angel who had a bowl says "Come, I will show you the BRIDE, the wife of the Lamb..." Is it merely a coincidence that the bride has made herself ready only after (and immediately after) the harlot is judged? 

8) Jerusalem is referred to as both a harlot and the Lord's bride. 

Isaiah 1:1 The vision of Isaiah the son of Amoz, which he saw concerning Judah and Jerusalem... 21. How the faithful city has become a harlot, she that was full of justice! Righteousness lodged in her, but now murderers. Ezekiel 16:2 "Son of man, make known to Jerusalem her abominations..." (read whole chapter) 

Jeremiah 2:2 "Go and proclaim in the hearing of Jerusalem, Thus says the LORD, I remember the devotion of your youth, your love as a bride, how you followed me in the wilderness, in a land not sown... 20. "For long ago you broke your yoke and burst your bonds; and you said, 'I will not serve.' Yea, upon every high hill and under every green tree you bowed down as a harlot. (see Jer.3.) 

Revelation 21:9..."Come, I will show you the Bride, the wife of the Lamb." 10 And in the Spirit he carried me away to a great, high mountain, and showed me the holy city Jerusalem...  

9) Just before the 7th trumpet, the two witnesses/prophets are slain in Jerusalem (see Rev. 11:8 above.) Just after the 7th trumpet is sounded, an angel declares, "Fallen, fallen is Babylon the great..." (Rev. 14:8.) Is it just a coincidence, or are the two events (prophets being slain and Babylon being judged) related, possibly being a fulfillment of Matt. 23:34-35? 

Matthew 23:34 Therefore I send you prophets and wise men and scribes, some of whom you will kill and crucify, and some you will scourge in your synagogues and persecute from town to town, 35 that upon you may come ALL the righteous blood shed on earth...  

10) It seems that Jerusalem and New Jerusalem have a lot in common, or perhaps they are one and the same. 

Isai 52:1 Awake, awake, Clothe yourself in your strength, O Zion; Clothe yourself in your beautiful garments, O Jerusalem, the holy city. For the uncircumcised and the unclean Will no more come into you... 7 How lovely on the mountains Are the feet of him who brings good news... 60:3 "And nations will come to your light, And kings to the brightness of your rising... 11 "And your gates will be open continually; They will not be closed day or night, So that [men] may bring to you the wealth of the nations, With their kings led in procession. 

Nahu 1:15 Behold, on the mountains the feet of him who brings good news, Who announces peace! Celebrate your feasts, O Judah; Pay your vows. For never again will the wicked one pass through you; He is cut off completely.  

Reve 21:2 And I saw the holy city, new Jerusalem, coming down out of heaven from God, made ready as a bride adorned for her husband. 3 And I heard a loud voice from the throne, saying, "Behold, the tabernacle of God (Rev 13:6) is among men, and He shall dwell among them, and they shall be His people, and God Himself shall be among them... 10 And he carried me away in the Spirit to a great and high mountain, and showed me the holy city, Jerusalem, coming down out of heaven from God... 24 And the nations shall walk by its light, and the kings of the earth shall bring their glory into it. 25 And in the daytime (for there shall be no night there) its gates shall never be closed; 26 and they shall bring the glory and the honor of the nations into it; 27 and nothing unclean and no one who practices abomination and lying, shall ever come into it, but only those whose names are written in the Lamb's book of life.  

It almost seems as if Jerusalem herself is "born-again"! 

11) Why have a "New Jerusalem" if the old one is still around? 

12) What is the big mystery in "Mystery Babylon" if it really is the same as historical Babylon? 

13) Zechariah 14:3-5 describes a day when Jesus goes to fight the enemies of Israel (Armageddon;) the Mount of Olives is split in two (earthquake?) after His feet touch it; and "you shall FLEE ..." Could this flight be in response to His command to "Come out of her, my people..." (Rev. 18:4) or "Depart, depart, go out from there" Isa 52:11? Could this earthquake be the same as the earthquake which divides the "great city" into three parts after the pouring out of the seventh bowl (Rev. 16:17-19) which also makes mention of the demise of Babylon? 

14) Compare Ezekiel 16 and Revelation 18!!!! 

I don't really know who Mystery Babylon is. That takes wisdom (Rev. 17:9.) Jerusalem would politically need to become a world capital of sorts (17:18), maybe moving the U.N. there. It would also need to become more of a religious capital (18:9), perhaps moving the Vatican there. Maybe that is how the mother-child worship (thus refering to her as "Babylon") comes to be included in her harlotries. I can't be sure yet, but I just don't feel comfortable with the other explanations I've heard. Just as there were prophecies of Jesus which were only understood in hind sight (Ps 22:16-18; 34:20; 69:21 etc), my guess is that there are other prophecies in the scriptures (maybe even in Psalms) pertaining to Mystery Babylon which will point to her true identity in time for us to heed the Lord's command in Rev. 18:4 to