And by day:
Now, some facts.
The tower weighs around 10,000 tonnes.
There are just over 18,000 metallic parts in the tower, held together by 2.5 million rivets.
They were assembled by 121 workers, while 50 engineers and designers produced the blueprints.
It shrinks by about six inches in cold weather, and can grow by six inches on a sunny day.
It's painted with 60 tons of paint every few years to stop it rusting.
It sways a couple of inches in the wind.
It's the most-visited paid monument on Earth.