Revelation 21:14

12And had a wall great and high, and had twelve gates, and at the gates twelve angels, and names written thereon, which are the names of the twelve tribes of the children of Israel:

13On the east three gates; on the north three gates; on the south three gates; and on the west three gates.

14And the wall of the city had twelve foundations, and in them the names of the twelve apostles of the Lamb.

15And he that talked with me had a golden reed to measure the city, and the gates thereof, and the wall thereof.

16And 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.