Revelation 21:13-16

There were three gates on the east, three on the north, three on the south, and three on the west. The walls of the city were built on twelve foundation stones, and on the stones were written the names of the twelve apostles of the Lamb. The angel who talked with me had a measuring rod made of gold to measure the city, its gates, and its wall. The city was built in a square, and its length was equal to its width. The angel measured the city with the rod. The city was 1,500 miles long, 1,500 miles wide, and 1,500 miles high.