Mike Kennelly's Landguard Fort for Unreal(TM)

The Caponier

All but one of the five corners of Landguard fort are bastions - projections from which flanking fire can be directed along the curtain walls.

The Caponier is a covered passage projecting out from the fifth corner into the moat, again to give the opportunity to lay down flanking fire. At Landguard an entrance was cut into the side of the Caponier to provide access from Darell's Battery, making it somewhat less secure.

Historical note:
When I was a kid I climbed onto the roof of the caponier and got stuck.

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