When the fifth bowl is poured out, the kingdom of Antichrist will become darkened (Rev. 16:10-11).
When the sixth bowl is poured out, the great river Euphrates will be dried up, and the way of the kings from the rising of the sun will be prepared (Rev. 16:12). In Revelation 9:14-16 we read that the four angels bound at the great river Euphrates will be loosed to stir up the kings to send their armies, the two hundred million horsemen, and in Revelation 16:12 we are told that at the outpouring of the sixth bowl, the water of the Euphrates will be dried up so that these kings and their armies may pass over it. Hence, the sixth trumpet and the sixth bowl are related to each other.
Then there will be the gathering for the war at Armageddon. This war will be waged by Antichrist, his false prophet, the ten kings, and their armies (Rev. 16:13-16), who will be defeated by Christ and His overcomers (Rev. 17:12-14; 19:11-21), in the treading of the great winepress of the fury of God (Rev. 14:17-20; Isa. 63:2-3).
The seventh bowl will be the greatest earthquake and the great hail of the exceedingly great plague (Rev. 16:17-21).
The city of Jerusalem and the cities of the nations all will fall (Rev. 16:19a).
The physical Babylon the Great, the city of Rome, will be destroyed (Rev. 16:19b).
Every island will flee, and mountains will not be found (Rev. 16:20).
The weight of every hailstone will be a talent (Rev. 16:21). A talent equals about one hundred pounds.
(All the above positive and negative items of the seventh trumpet should take place on the same day, that is, the last day of the great tribulation.)