Revelation 21:16-17

16The city was laid out like a square, as long as it was wide. He measured the city with the rod and found it to be 12,000 stadia That is, about 1,400 miles or about 2,200 kilometers in length, and as wide and high as it is long. 17The angel measured the wall using human measurement, and it was 144 cubits That is, about 200 feet or about 65 meters thick. Or high