Imagine the foundation of the walls of a city looking like this.   Here's how the Apostle John
described what he saw in the book of the Revelation, chapter 21:12-14,19-23;27

"It had a great high wall, with twelve gates, and at the gates twelve angels; and
names were written on them, which are those of the twelve tribes of the sons of Israel.
There were three gates on the east and three gates on the west.
And the wall of the city had twelve foundation stones, and on them were the
twelve names of the twelve apostles of the Lamb.

The foundation stones of the city wall were adorned with every kind of precious stone.
The first foundation stone was jasper; the second, sapphire; the third, chalcedony;
the fourth, emerald; the fifth, sardonyx; the sixth, sardius; the seventh, chrysolite;
the eighth, beryl; the ninth, topaz; the tenth, chrysoprase; the eleventh, jacinth;
the twelfth, amethyst.

The twelve gates were twelve pearls; each one of the gates was a single pearl.
And the street of the city was pure gold, like transparent glass.  And I saw no temple in it,
for the Lord God, the Almighty, and the Lamb, are its temple.  And the city has no need of
the sun or of the moon to shine upon it, for the glory of God has illumined it,
and its lamp is the Lamb.

And nothing unclean and no one who practices abomination and lying,
shall ever come into it, but only those whose names are written in the Lamb's book of life."

Come, let's go up to that 'pearly gate' and see if we can see what John saw . . .