Anyone seeing 216 randomly like me lately?    Why is the hallway from the Eastern Gate of the City of God 216 feet long?   And why is the wall of the City of God 216 feet thick?    It is to show the saints we are married to Him forever, and "For I hate divorce," says the LORD, the God of Israel." 

http://www.rapture5770-5775.com/visittoheaven.htm
"When the raptured saints come in sight of this magnificent City and that beckoning eastern gate, and when the glorious spiritual reality of our eternal Home dawns upon our glorified sight, we will be so filled with divine ecstasy that we will shout hallelujahs and praises to God like we never knew could come from our innermost being.
It will be the heavenly fulfillment of what happened when Jesus rode triumphantly into the earthly city of Jerusalem.  On earth He was rejected, but in Heaven we will all be received.
St. John said each gate was a pearl and all twelve gates are never shut.  A pearl is milk-white and translucent; we can see into a pearl, but we cannot see through it.  The heavenly Throne of God and of Jesus has also a bright white semi-transparent appearance like a pearl.  The gates are like pearl because they are concentrated white light.  We can see into this light but we cannot see through it.  We can, however, pass through this gate of pearly light.  That's why it is said to be never shut.  But it does not stand open as a door on earth stands open.  (Jesus on earth passed through closed doors in His glorified body.)
After we enter through the gate of pearly white light, we see a huge hallway.  With its high vaulted ceilings and wide corridor, it is about 216 feet long, because the wall of this City is 216 feet thick. There are no lighting fixtures here.  The light comes from the Throne of God and begins as a very bright white light.  Then as this light is diffused through, and reflected from, the gem-like structure of this City, there emerges a rainbow spectrum which is the blending of five major colors: gold, blue, purple, red and green."