"Dear councillors, you know that I have some affinity with the art of building, maintaining and destroying castle, the art of poliorcetics. Since the construction of the citadel is closer to inception, I decided to share my knowledge in a practical way with you and His Majesty.
D'Armagnac points at the parchments.
"The incanubulum per se will be in royal hands and so will not be available for you to read. So are some other documents containing sensitive information. Still, here is a brief summary of the plan I humbly suggest for the citadel. Here for you perusal. His Majesty will decide if it even worth reading, let alone discussed."
Treatise of poliorcetics applied to Crypto-Kingdom
Dear council members,
This treatise was written by His Excellence the Right Honourable Earl David d'Armagnac in the year of our Lord 1462. This extensive volume is meant as a general guide to build and defend the capital of Crypto-Kingdom against invaders of any kind. It draws upon d'Armagnac's extensive knowledge of poliorcetics (the art of attacking and defending a castle) and is written in a deliberately pragmatic way. It is not a monograph or a general consideration on the building of castles, but a guide in building and defending this very citadel.
Below is a summary of the Treatise.
Terminology
- Donjon: the main building, reminiscent of ancient stronghold, not large enough for withstanding full-fledged, month-long sieges. Still symbolically, architecturally and defensively important, since it is impressive and testify for the power of the castle-owner, can host a lot of people and, by virtue of its height, allows one more line of defense to retaliate against the besiegers
- Castle: an extended fortification made of a donjon plus a court and building and surrounded by one or more walls/ To be considered a castle, a building must fulfill these requirements, (according to Schwabenspiegel.
- a ditch deep enough that one cannot displace earth out of the ditch just with a showel
- a wooden or stone building of more than three storeys with wall ending with a parapet (the parapet doesn't not need to be crenelated)
- a bailey surrounded by either by a curtain wall high enough to prevent a horseman to touch the top or by a curtain wall with a parapet (crenelated or not) - Palace: a large building with no defensive purpose. A lot of castles became palaces with time.
- Citadel: a fortified city
Overview
The citadel doesn't benefit from any topographical advantage, such as a narrow entrance, a mountain on its back or water access. It thus follow the traditional motte-and-bailey architecture, the motte being a raised earth mound built with the earth extracted from the construction of the moat.
It is entirely made of stone and, with the exception of the donjon, all towers are horseshoe-shaped, so that the external side better protect against projectiles, which rip off the curvature of the towers, while the rectangular internal side gives more internal space and a better battling platform
The citadel is a concentric castle. That is, it uses an onion-like structure, with two layers of wall before reaching the donjon
Layers
- layer I: six-storeys pentagonal donjon, atop the motte. It has an elevated entrance[1] at the second floor, accessible though a wooden, easily destructible, staircase and is surrounded by a chemise, which makes it very difficult for a sensible amount of soldiers to attack at the same time (similar to Thermopyles). Place of last-resort defence, very thick walls, food reserve in the dungeon, small rooms. Behind and protected by the donjon is the palas, place of residency.
- layer II: inner bailey (higher court) with a well and premium dwellings
- layer III: inner curtain wall (2.50 meters thick, 12 meters high), with some posterns for sorties or escaping. The base of the internal curtain wall and the donjon may be built - this would not help the attackers much and would provide substantive incomes in times of peace.
- layer IV: outer bailey (base-court), with workshops, livestock stalls and stables; storage facilities such as barns, sheds and granaries, brewery, bakehouse, cistern as well as quarters for servants such as maids and farm workers. Should the besiegers arrive here, they would be in a killing zone, since defenders would attack from both the inner curtain wall and the hollowed outer curtain wall. Plus, reaching the entrance in the inner curtain wall require following a chemin de défilement meant to maximise exposure to defenders' attacks.
- layer V: outer curtain wall (6 meters thick because of inside corridors, 7 meters high, lower than the inner curtain wall, itself lower than the donjon so that the three structures can retaliate at the same time) with a gatehouse including an ankle breakers-equipped flooring on the drawbridge[2]. The base of the wall is free of any construction or noticeable vegetation, to ensure a clear view for the defenders and also given a stone skirt around its base to deter undermining. The walls are particularly thick because they are hollow: they host soldiers who can flank the besiegers should they enter the outer bailey (the arrow slits are only in the inside-facing wall). Like the inner curtain wall, the outer curtain wall as posterns, none of them giving access to the "wall tunnels".
- layer VI: water-filled moat[3], to prevent further undermining as well as to make it difficult for siege weapons to come close enough. The scarp and counterscarp (respectively inner and outer shore of the moat) are filled with semi-immerged trous de loup and caltrops to hinder enemies. Additionally, a tunnel runs below the counterscarp, allowing soldiers to shoot attaquants - only small doors communicate with the outer bailey, rendering an intrusion from the counterscarp particularly challenging and these tunnels are only used in time of war, since they are unpleasant and humid. Fish living in the moat are usually hardly edible, because of the poor quality of the water - the latrines empty here.
- layer VII: barbican[4], if deemed necessary. It could benefit from a bent entrance[5], a complex, chicaned entrance meant to hinder the progression of troops but it would be at the expense of some real estate and would only make sense it the citadel is not supposed to be used much in peace time, as the bent entrance makes daily traffic difficult.
- layer VIII: wooden stockade.
- layer IX: open-ended jousting area, making any besiegers an easy target. In peace time, the jousting area is used for jousting, celebration and as a marketplace.
Curtain walls
The tops of both curtain walls includes battlements with crenelated parapets (with mantlet-protected arbalestinas on 0,48 cm thick merlons), chemins de ronde (walkways) and full-lenght closed machicolations (other example and another) as well as gargoyles to evacuate the rain. The curtain wall ended up in a glacis, to make approaches and ladderscaling harder and to increase the lethality of stone thrown from machicolations) Corner towers (the castle is too small for flanking towers) have embrasures with cross-shaped arrowslits (arbalestinas) with oillets (a larger opening at the bottom to allow a better observation when not shooting) as well as a bartizans for reducing dead angles. Straight staircases large enough for two persons lead to every courtine (example)
Both curtain walls have a single entrance, a heavily guarded gatehouse with two projecting towers, one on each side of the entrance, to prevent blind spots. The entrance itself is a long corridor with a portcullis at each end; the corridor itself sports meurtrières – a pierced ceiling where defenders can throw stone and fire-heated sand - as well as arrowslit on the wall. Provision is made for accommodation of a rotating team of soldiers.
Projectiles
Out of arrows and particularly bolts (crossbows are better at defending a castle than bows and have a range of 150 m, source)), projectiles (from murderholes and machicolations) include stone, boiling water (rare, boiling oil being almost non existant); quicklime and even beehive (Blâmont, 1475).
Staircases
Every inside staircase is a counterclockwise spiral staircase. Spiral staircases are the most dense and being counterclockwise (from the point of view of someone going down), they make it difficult for right-handed attackers to fight
Here stops the summary of the Treatise. The full treatise goes into much further details and also address the topic of military tactics and sensitive information.
For the betterment of Crypto-Kingdom,
d'Armagnac
1. Examples of elevated entrances
http://media-cdn.tripadvisor.com/media/photo-s/02/1c/be/dc/way-in-up-the-stairs.jpg
http://upload.wikimedia.org/wikipedia/commons/6/60/Warkworth_Castle's_keep,_2007.jpg
http://l-atelierdemaminette.blog50.com/images/medium_donjon_et_chemin_de_garde.JPG
http://gailingis.com/wordpress/wp-content/uploads/2013/08/Keep-details-full-page-at-Dover-castle-England.jpg
http://www.crdp-strasbourg.fr/data/lcr/chateaux/images/big-donjon1.jpg (show that the dunjon is located at ground floor, with the entrance of the donjon is at first floor)
http://upload.wikimedia.org/wikipedia/commons/thumb/7/7c/Donjon.Chateau.Gaillard.png/440px-Donjon.Chateau.Gaillard.png (particularly high entrance)
2. Examples of drawbridges
http://thumb7.shutterstock.com/display_pic_with_logo/195460/108116621/stock-photo-drawbridge-at-an-medieval-italian-castle-108116621.jpg (small)
http://www.featurepics.com/FI/Thumb300/20110217/Castle-Drawbridge-1787698.jpg (large with swipe-beam)
http://s3-eu-west-1.amazonaws.com/lookandlearn-preview/M/M815/M815849.jpg (how to raise a drawbridge)
3. Examples of water-filled moats
http://www.exploring-castles.com/image-files/beaumaris_castle_autumn.jpg
http://masonmyers.com/wp-content/uploads/2012/08/canstockphoto3921322.jpg
4. Examples of barbican
http://www.castlesandmanorhouses.com/castles/pics/carcpicchateau02.gif
http://visual.merriam-webster.com/images/arts-architecture/architecture/castle.jpg
5. Example of bent entrance
http://carneycastle.com/Dinefwr/model1.jpg