Babylon the Great was remembered before God, to give her the cup of the wine of His fierce wrath...
Revelation 17 begins with an interlude; a pause from the events of the great tribulation period. One of the seven angels with one of the seven bowls took John by the spirit, into the wilderness, a barren and desolate desert to show John why Babylon was singled out for judgement: 17:1-3. Here John sees a woman dressed in scarlet and purple, adorned with the riches of the world carried upon a scarlet beast kingdom, which has seven heads and ten horns. John details that the entire kingdom is full of blasphemy - blasphemous men and women who mock the God of heaven, while worshiping a false and malicious god.
The woman sits upon many waters - seven world kingdoms, that belong to the beast, demonstrating her ruling power over the kings of the earth, and many peoples, multitudes, nations and tongues. She is drunk on power and the golden cup in her hands is full of vile and abominable things. The name written on her forehead is one of mystery; Mystery, Babylon the Great, the Mother of Harlots and Abominations of the Earth; suggesting a middle east location.
John also witnessed a plot of vengeance, a conspiracy, against the woman, organized by ten horns / ten kings who rise from the head of Daniel's fourth beast; placing the fourth beast into the tribulation period. Daniel's fourth beast is an amalgamation of three previous beast kingdoms which ruled the middle east: the lion, the bear and the leopard: Daniel 7:7,19; Revelation 13:2a. The angel identifies the woman, Babylon the Great, as that great city, who rules over the kings of the earth in verse 18.
After John is shown all these things, a second angel comes down from heaven having great power and, lightens the earth with his glory:18:1. John isn't taken in the spirit, when the second angel arrives, indicating that John and the first angel, are still in the wilderness, where the beast, and the woman are located: 17:3.