The Nauvoo Temple was finished in 1846, but later destroyed by an arsonist. The remaining stones were toppled by a tornado. The temple was re-built in 2002 with the same exterior design. I will not attempt to explain the symbolism here; rather, this post will include links to another blog that does an excellent job explaining the meaning behind the architecture.
The temple included "moonstones."
The tower once had an angel weather vane, but the re-designed temple replaced the weather vane with a classic Angel Moroni statue.
The five-pointed star was said to represent Venus: the Morning Star.
The outer gates.
Joseph and Hyrum Smith were said to have paused
near the temple before surrendering to arrest in Carthage.