We don't know. Because St John doesn't tell us.
He tells us that the new Jerusalem, the perfect city, has pearly gates.
But when he tells us that, the new Jerusalem is on earth.
Trick question that I had the Jehovah's Witnesses ask me last week - they clearly walked straight past the sign saying "The Beaker Folk of Husborne Crawley - The modern Cyber-Coenobitic Community" and then tried to bandy their impoverished theology around with a woman wearing an official Archdruidical hat (replica hats available in the Beaker Bazaar).
"Where do you think everyone will end up?"
And the answer they're hoping for, when addressing a middle-aged woman, is "heaven". Then they go "aha"! And tell you that's only 144,000 people and do I feel that lucky punk?
Instead of which they got 15 minutes on my theology of a totally-renewed Creation. A new heaven and a new earth. A place where hearts and minds and bodies are resurrected and healed. Where those pearly gates are always open, as it says in the good book, so anyone that wants can come in. A place where heaven has come down to earth.
A place where God walks with God's people and the water of life is pure and the tree of life is once more given to us. And God will reign and the fruit that we stole from the tree of knowledge in a mythical garden long ago will mean that we know everything is now good and we will know as we are known and love as we are loved.
And through the wars of this world and a tree of Death on which the author of life died, there will be no more death and no more war.
The Book of Revelation isn't a history book of the future. It's a promise. It says hang on. All you can see and hear now are just labour pains. But a new day is coming when the weak are strong and the poor are rich and the Prince of Peace will be with us all.
And we are called to be saints. From the greatest to the littlest, God can pick us up and say you are loved and I have great things in store for you. I can do new things you have never imagined.
So as God's loved ones, we can work to make the present world a little more like the one to come. And wait with all heaven and earth for God's promises to be fulfilled.