Tag Archives: Tower of London

The Anatomy of a Castle – The Keep

Keeps are tall towers. They’re typically located on the opposite side of the bailey to the gatehouse, or in the centre of the castle.  Early keeps, like the castles they stood in, were designed to intimidate the locals. They were also called donjons, from the Latin dominus – lord, or master.  They were designed to be strong. It should be noted that not all towers are keeps. Towers on outer walls are just towers.

The best-known keep in England is the White Tower in the Tower of London. It was built in the 1080s by William the Conqueror and was whitewashed on the orders of Henry III in 1240.

When I visited Portchester Castle earlier in the year, I couldn’t get all of the keep into the frame to take a photograph, so I made a short video.

The keep at Portchester is not opposite the gatehouse. They are on diagonally opposite corners of the castle walls, which more or less form a square. In the 1130s the keep was built to a height just above the walls. Two more stories were added by the 1150s and a final floor in the 1320s. In the opening seconds of the video you can see the holes in a wall where the fourteenth-century staircase to the first-floor entrance used to be. They’re on the bottom right of the picture.

There are latrines and fireplaces in the keep, which show that it was intended for domestic use, rather than storage or primarily for defence.

Keeps were the last line of defence of a castle. They were made to be difficult to get into and once in it wasn’t easy for the enemy to get much further.

Stairs in keep

The stairs in the keep, Portchester Castle

The stairs are narrowest on the right-hand side by design. The attackers would not have been able to use weapons in their right hands effectively, whilst the defenders would. The defenders would also have the advantage of being above their attackers.

Fortunately for me, and most visitors, there are modern, wooden stairs within the keep.  You only need to use the spiral stairs if you want to get to the very top of the keep. I was happy enough to enjoy the view from the highest point I could reach without using them.

Landgate from keep 2

Landgate and Portsmouth from the keep, Portchester Castle

This is what remains of the keep at Old Sarum. It’s directly opposite the main gate. The gap you can see to the right is the postern gate and we’ll get on to that in a later post.

Tower and courtyard house, Old Sarum

Tower and courtyard house, Old Sarum

Old Sarum is on top of a hill. One of the reasons for putting a tall tower on top of a hill was obviously to make an impression on those who saw it. The rooms at the bottom of the keep were probably used for storage. They’re at ground level and the main entrance to the keep was above them, reached by steps. This was a feature of most keeps.

Steps to tower, Old Sarum 2

Steps to tower, Old Sarum

The room on the first floor of a keep was probably used by the lord of the castle to receive visitors and would have been decorated to impress.



Castle – Marc Morris

Portchester Castle –  John Goodall

Old Sarum –  John McNeill


April Munday is the author of the Soldiers of Fortune and Regency Spies series of novels, as well as standalone novels set in the fourteenth century.

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