Portcullis

A portcullis (from the French porte coulissante or gliding door) is a latticed grille made of wood, metal or a combination of the two. Portcullises fortified the entrances to many medieval castles, securely closing off the castle during time of attack or siege. Each portcullis was mounted in vertical grooves in castle walls and could be raised or lowered quickly by means of chains or ropes attached to an internal winch.

There would often be two portcullises to the main entrance. The one closer to the inside would be closed first and then the one farther away. This was used to trap the enemy and often, burning wood or fire-heated sand would be dropped onto them from the roof or murder-holes. Hot oil, however, was not commonly used in this manner, contrary to popular belief, since oil was extremely expensive. There were often arrowslits in the sides of the walls, enabling archers and crossbowmen to eliminate the trapped group of attackers.

The Burgs on Nilfeheim contain portcullis used mostly ceremonially since flyers can easily go over a Burg's walls.