Revelation 21:10 - 13...10And he carried me away in the Spirit to a mountain great and high, and showed me the Holy City, Jerusalem, coming down out of heaven from God. 11It shone with the glory of God, and its brilliance was like that of a very precious jewel, like a jasper, clear as crystal. 12It had a great, high wall with twelve gates, and with twelve angels at the gates. On the gates were written the names of the twelve tribes of Israel. 13There were three gates on the east, three on the north, three on the south and three on the west.
Revelation 21:15 - 17...15The angel who talked with me had a measuring rod of gold to measure the city, its gates and its walls. 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 in length, and as wide and high as it is long. 17He measured its wall and it was 144 cubits thick, by man's measurement, which the angel was using.