How do the cranes used to build tall buildings get put in place?

Question

They seem to be the tallest thing around, so what put them up?

Answer 1

They are self-elevating. They jack themselves up.

It was the invention of the self-elevating crane and the self service elevator which made popular tall buildings.

In older cities, such as Paris, the height of a building was limits by the number of flights of stairs people were willing to climb.

Answer 2

Large cranes are built in sections imagine like an erector set. When there is a large building to be built the crane arrives in smaller easier to manage pieces and assembled on site.

Answer 3

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