Revelation 21:15-16

Verse 15-16 “And he that talked with me had a golden reed to measure the city, and the gates thereof, and the wall thereof. And the city lieth foursquare, and the length is as large as the breadth: and he measured the city with the reed, twelve thousand furlongs. The length and the breadth and the height of it are equal.”

Now we are told that the city is in the shape of a square and that the length and width and height are all the same. The angel who has been talking with John takes a golden reed (a measuring rod) to measure the city to show John how large it is. The measure is given as 12,000 furlongs. This does not specify whether that is the perimeter measurement or the length of one side. Most assume it is the length of one side, as 1) it is then mentioned that the length, height, and width are all equal, which implies that this is the measurement that should be applied to each, 2) God usually does not incorporate math problems into his descriptions for us to figure out the measurements, but gives the measurements themselves, and 3) the city must be big to accommodate all the saints from the beginning of time. If taken that the length is twelve thousand furlongs, it is 1500 miles or 2414 km in our terms of measurement. This would appear to be a cube with every side measuring 1500 miles under that interpretation. While it does not say it is in the shape of a cube, I believe that is its indicated shape rather than a pyramid as some seem to think it is. First, the pyramid seems to be a shape that the occult uses, while nothing in God’s design of the temple ever resembled anything like a pyramid. However, the cube shape is used in the temple. This city, if placed on the earth would cover a huge area. If one were to start at the southeast corner of Alabama and draw a straight line over through Mexico to the place where the western boundary of Arizona would be if one were to draw the line down through Mexico, then draw a line straight up one third of the way through Alberta, Canada, straight across to the province of Ontario, and then back down to the southeast corner of Alabama, one would have the approximate area that this city would cover on this planet. For readers in Europe, if one started at the southwestern most tip of Spain, went north past the western part of Ireland until even with Edinburgh, Scotland, then east until halfway through (and above) Poland, then down until east of Italy and back over to the starting point in Spain making a square, you would have the approximate size of this city. For Australians, draw a box around the entire continent, then take off what you need to from the left side (about half of Western Australia) to square it off. I think everyone can picture the size now, (even though I may not have done your continent) and that I do not have to do this for every continent. That would just be the length and width without considering the height. Now it can be seen why during the millennium it orbits the earth rather than coming down at that time. It awaits a new earth, which one supposes will have to be much larger than the present earth, to host it. Not only that, this city will extend 1500 miles out into space if the height is the same. As there are many ideas on this subject, and we do not really have enough to be dogmatic about any one idea, I will present another idea I read. One person came up with the idea that this is not a city, but a walled garden like Eden, as we are later told of the trees and river in the middle of the city. They believe that Mt. Zion is the center peak of that city and that is why the city is considered 12,000 furlongs high. The top of the peak would be that high, therefore the city must be that high to incorporate the mountain. I do not think this is a viable idea though, as clearly the place is a place of habitation for millions of people and not simply a garden. There are many mansions there, plus for a mountain to go 1500 miles into the air, it would necessitate using up the entire mass of the base of the city to accommodate the incline, not leaving any level garden space or space for homes. Also there is the problem that if it is to orbit the earth for the millennia, it would not make sense for it to be a garden. It would make sense for it to be an enclosed cube. There would need to be a way to keep an atmosphere for the inhabitants while in space, so an enclosed cube would do that. As the city is made of transparent gold, it would not seem so enclosed, and God's light would shine out from it, illuminating it like the sun. For people who watch Star Trek, it might be on the idea of a Borg cube which had multiple living levels. Possibly the garden (which we will see later) is in an open center area where God dwells on His throne and there are levels around this center. It is not as if there are simply apartments on a balcony around a narrow edge, as the area is 1500 miles in length. Even a garden as large as 100 miles square in the middle would leave huge amounts of area extending outward for mansions and grounds on multiple levels. When the city comes down to rest on the earth, it would still extend way out into space, so being enclosed would still give it an atmosphere, unless the new world's atmosphere extends that far out from the planet. One’s imagination can come up with all sorts of possibilities, but there is no way to know as God simply has not told us.

Just for the sake of consideration that the measurement is the perimeter and not the length, then each side would be only one fourth of that length or 375 miles (603.5 km). That would be a far smaller city, although the mileage out into space would still seem to be problematic.