ELI5: Explain Like I'm 5

Portcullis

A portcullis is a gate that is made out of metal bars or wooden beams. It is used to close off a passageway to keep people, animals, or even enemies out. It was used in castles to protect people from intruders or attackers. You could raise and lower the gate with a rope or a chain. The portcullis would often have spikes to help protect the inside of the castle.
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