Janet Willis presents evidence that New Jerusalem is shaped like a mountain.
God graciously gave believers a stunning picture of our future home (Rev 21:2). A whole city will come down from the sky. Nothing in the visual experience of humans quite compares to this. But can we know the overall contour of God’s city? Most assume God’s city is shaped like a cube like the Holy of Holies. But when we examine the whole of Scripture, we see many clues that the shape of New Jerusalem is more like a pyramid. Throughout the Bible, God’s dwelling place is often called “the holy mountain of God.” The case for a pyramid-shaped New Jerusalem gets even stronger when we take a close look at what occurred at Mt. Sinai in the book of Exodus. Then we’ll see how the book of Hebrews compares the mountain of Sinai with the heavenly Jerusalem (Heb 12:18-24). We will then compare the full layout of Ezekiel’s vision (Ezek 48), including the city and compare it with the layout at Mt. Sinai. The harmony is amazing! Comparing Scripture with Scripture provides compelling evidence that the city John saw, New Jerusalem, is shaped like a mountain.
See her magazine article on this topic here.