Wumen Gate
The gate is 35. Meters high. It looks like a "TT" from above it. As the obverse gate of the palace, the Wumen Gate looks quite dignified and solemn.
In ancient time, the men who gets the first 3 places in imperial examinations will go through the middle gate of Wumen for one time. The queen can go through the gate for once when she is married with the emperor. The gate is designed for the emperor's get into and outside, so it's usually closed. The goverment officers and dukes go to the palace through the north and south gates of the Wumen Gate.
We often hear in movies, that the person who is going to execute death penalty is being killed at Wumen, but that's not true. In fact, they're killed at the doorway of Vegetable Market.