Revelation 21:14-16

Amplified Bible

¹⁴ And the wall of the city had twelve foundation stones, and on them the twelve names of the twelve apostles of the Lamb (Christ).

¹⁵ The one who was speaking with me had a gold measuring rod to measure the city, and its gates and its wall. ¹⁶ The city is laid out as a square, its length being the same as its width; and he measured the city with his rod—twelve thousand stadia (about 1,400 miles); its length and width and height are equal.