Duchy buildings

Crusader Kings III

Buildings

Economic buildings

Military buildings

Fortification buildings

County buildings

Duchy buildings

Special buildings

Duchy buildings can only be constructed by a Feudal, Clan or Administrative ruler in the de jure capital of a  Duchy and can only be used if the character holds the associated Duchy Title. Each duchy can only support one such building and if the duchy capital is relocated the building is removed. All duchy buildings take 5 years to construct or upgrade and most have 3 levels.

• Level 1 buildings cost 600  Gold
• Level 2 buildings cost 900  Gold
• Level 3 buildings cost 1200  Gold

Duchy buildings

Building type	Level 1 effects	Level 2 effects	Level 3 effects	Requirements	Description
Archery Grounds	Holding -50% Cost for hosting Grand Tournament Archery Contest +30% Stationed Archer Damage +10% Stationed Archer Toughness +30% Stationed Skirmisher Damage +20% Stationed Skirmisher Toughness +20% Stationed Skirmisher Pursuit +20% Stationed Skirmisher Screen +20% Stationed Archer Cavalry Damage +10% Stationed Archer Cavalry Toughness +20% Stationed Archer Cavalry Pursuit +20% Stationed Archer Cavalry Screen Realm -6.00% Men-at-Arms Maintenance	Holding -50% Cost for hosting Grand Tournament Archery Contest +45% Stationed Archer Damage +12% Stationed Archer Toughness +45% Stationed Skirmisher Damage +30% Stationed Skirmisher Toughness +30% Stationed Skirmisher Pursuit +30% Stationed Skirmisher Screen +30% Stationed Archer Cavalry Damage +12% Stationed Archer Cavalry Toughness +30% Stationed Archer Cavalry Pursuit +30% Stationed Archer Cavalry Screen Realm -8.00% Men-at-Arms Maintenance	Holding -50% Cost for hosting Grand Tournament Archery Contest +60% Stationed Archer Damage +15% Stationed Archer Toughness +60% Stationed Skirmisher Damage +40% Stationed Skirmisher Toughness +40% Stationed Skirmisher Pursuit +40% Stationed Skirmisher Screen +40% Stationed Archer Cavalry Damage +15% Stationed Archer Cavalry Toughness +40% Stationed Archer Cavalry Pursuit +40% Stationed Archer Cavalry Screen Realm -10.00% Men-at-Arms Maintenance	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	Dedicated archery ranges allow the common folk to train with bows, and experienced archers to hone their skills.
Crown Smithies	Holding -50% Cost for hosting Grand Tournament Duel Contest +15% Stationed Heavy Infantry Damage +30% Stationed Heavy Infantry Toughness +15% Stationed Spearmen Infantry Damage +30% Stationed Spearmen Infantry Toughness Realm Increased Quality of Sponsored Inspirations Enables the Superior Armaments Travel Option -6.00% Men-at-Arms Maintenance	Holding -50% Cost for hosting Grand Tournament Duel Contest +20% Stationed Heavy Infantry Damage +45% Stationed Heavy Infantry Toughness +20% Stationed Spearmen Infantry Damage +45% Stationed Spearmen Infantry Toughness Realm Increased Quality of Sponsored Inspirations Enables the Superior Armaments Travel Option -8.00% Men-at-Arms Maintenance	Holding -50% Cost for hosting Grand Tournament Duel Contest +25% Stationed Heavy Infantry Damage +60% Stationed Heavy Infantry Toughness +25% Stationed Spearmen Infantry Damage +60% Stationed Spearmen Infantry Toughness Realm Increased Quality of Sponsored Inspirations Enables the Superior Armaments Travel Option -10.00% Men-at-Arms Maintenance	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	Smiths in the employ of the crown forge weapons and armor for the royal guard, ensuring a steady supply of superior armaments.
Jousting Grounds	Holding -50% Cost for hosting Grand Tournament Joust and Horse Race Contest +20% Stationed Light Cavalry Damage +20% Stationed Light Cavalry Toughness +20% Stationed Light Cavalry Pursuit +20% Stationed Light Cavalry Screen +30% Stationed Heavy Cavalry Damage +30% Stationed Heavy Cavalry Toughness +30% Stationed Heavy Cavalry Pursuit +30% Stationed Heavy Cavalry Screen +20% Stationed Camel Cavalry Damage +20% Stationed Camel Cavalry Toughness +20% Stationed Camel Cavalry Pursuit +20% Stationed Camel Cavalry Screen +30% Stationed Elephant Cavalry Damage +30% Stationed Elephant Cavalry Toughness Realm -6.00% Men-at-Arms Maintenance	Holding -50% Cost for hosting Grand Tournament Joust and Horse Race Contest +30% Stationed Light Cavalry Damage +30% Stationed Light Cavalry Toughness +30% Stationed Light Cavalry Pursuit +30% Stationed Light Cavalry Screen +45% Stationed Heavy Cavalry Damage +45% Stationed Heavy Cavalry Toughness +45% Stationed Heavy Cavalry Pursuit +45% Stationed Heavy Cavalry Screen +30% Stationed Camel Cavalry Damage +30% Stationed Camel Cavalry Toughness +30% Stationed Camel Cavalry Pursuit +30% Stationed Camel Cavalry Screen +45% Stationed Elephant Cavalry Damage +45% Stationed Elephant Cavalry Toughness Realm -8.00% Men-at-Arms Maintenance	Holding -50% Cost for hosting Grand Tournament Joust and Horse Race Contest +40% Stationed Light Cavalry Damage +40% Stationed Light Cavalry Toughness +40% Stationed Light Cavalry Pursuit +40% Stationed Light Cavalry Screen +60% Stationed Heavy Cavalry Damage +60% Stationed Heavy Cavalry Toughness +60% Stationed Heavy Cavalry Pursuit +60% Stationed Heavy Cavalry Screen +40% Stationed Camel Cavalry Damage +40% Stationed Camel Cavalry Toughness +40% Stationed Camel Cavalry Pursuit +40% Stationed Camel Cavalry Screen +60% Stationed Elephant Cavalry Damage +60% Stationed Elephant Cavalry Toughness Realm -10.00% Men-at-Arms Maintenance	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	By having dedicated grounds for jousting, more riders and knights are encouraged to train and join the banners.
Leisure Palaces	Holding -50% Feast Cost +5 Renown from Grand Weddings -30 Stress from Grand Weddings Duchy +0.20 Monthly Control Growth +20% Control Growth Realm +5% Monthly Prestige +15% Stress Loss +5.0% Initial Hostile Scheme Success Chance +5.0% Initial Personal Scheme Success Chance	Holding -50% Feast Cost +25 Renown from Grand Weddings -65 Stress from Grand Weddings Duchy +0.30 Monthly Control Growth +40% Control Growth Realm +10% Monthly Prestige +25% Stress Loss +15.0% Initial Hostile Scheme Success Chance +15.0% Initial Personal Scheme Success Chance	Holding -50% Feast Cost +50 Renown from Grand Weddings -100 Stress from Grand Weddings Duchy +0.40 Monthly Control Growth +60% Control Growth Realm +15% Monthly Prestige +35% Stress Loss +25.0% Initial Hostile Scheme Success Chance +25.0% Initial Personal Scheme Success Chance	Manorialism innovation for level 1  Windmills innovation for level 2  Cranes innovation for level 3	While staying in one lavishly luxuriant castle is fine, having a few more to choose between never hurts.
Marches	Duchy +25% Supply Limit +2 Fort Level +20% Hostile Raid Time +25% Garrison Size +25% Levy Reinforcement Rate +5 Defender Advantage -10 Danger +15% Holding Taxes in Hills +15% Holding Taxes in Mountains +15% Holding Taxes in Desert Mountains	Duchy +50% Supply Limit +4 Fort Level +30% Hostile Raid Time +50% Garrison Size +50% Levy Reinforcement Rate +10 Defender Advantage -20 Danger +20% Holding Taxes in Hills +20% Holding Taxes in Mountains +20% Holding Taxes in Desert Mountains	Duchy +100% Supply Limit +6 Fort Level +40% Hostile Raid Time +100% Garrison Size +100% Levy Reinforcement Rate +15 Defender Advantage -30 Danger +30% Holding Taxes in Hills +30% Holding Taxes in Mountains +30% Holding Taxes in Desert Mountains	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	Marcher lords protect the borders with fortifications and local garrisons.
Military Academies	Realm Enables the Train Knights Travel Option -10% Men-at-Arms Recruitment Cost -2.50% Army Gold Maintenance +2 Number of Knights +25% Knight Effectiveness +1 Size of Men-at-Arms Regiments	Realm Enables the Train Knights Travel Option -20% Men-at-Arms Recruitment Cost -3.50% Army Gold Maintenance +4 Number of Knights +50% Knight Effectiveness +2 Size of Men-at-Arms Regiments	Realm Enables the Train Knights Travel Option -30% Men-at-Arms Recruitment Cost -5.00% Army Gold Maintenance +6 Number of Knights +75% Knight Effectiveness +3 Size of Men-at-Arms Regiments	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	Dedicated facilities for training officers and knights, improving their efficiency in combat.
Royal Armories	Holding -50% Cost for hosting Grand Tournament Melee Contest +15% Stationed Men-at-Arms Damage +15% Stationed Men-at-Arms Toughness Duchy +20% Levy Size Realm -2.50% Army Gold Maintenance	Holding -25% Grand Tournament Cost +20% Stationed Men-at-Arms Damage +20% Stationed Men-at-Arms Toughness Duchy +30% Levy Size Realm -5.00% Army Gold Maintenance	Holding -25% Grand Tournament Cost +25% Stationed Men-at-Arms Damage +25% Stationed Men-at-Arms Toughness Duchy +40% Levy Size Realm -10.00% Army Gold Maintenance	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	By having the crown provide weapons and armor to its soldiers, more peasants can 'volunteer' for the levy.
Royal Reserves	Holding Increased Hunt Success Chance +0.80 Monthly Tax Duchy +10% Development Growth +5 Popular Opinion	Holding Increased Hunt Success Chance +1.10 Monthly Tax Duchy +20% Development Growth +10 Popular Opinion	Holding Increased Hunt Success Chance +1.40 Monthly Tax Duchy +30% Development Growth +15 Popular Opinion	Manorialism innovation for level 1  Windmills innovation for level 2  Cranes innovation for level 3 Desert terrain Mountains terrain Oasis terrain Steppe terrain Wetlands terrain	A royal forest is a valuable source of wealth, allowing you to override the law of the land in a province, strip rights from the locals, then sell them back. Needless to say, the hunting is also excellent.
Siege Works	Holding +5 Stationed Siege Weapon Toughness +20% Stationed Siege Weapon Effectiveness Duchy +2 Fort Level Realm -15.00% Siege Weapon Maintenance -15.00% Siege Weapon Recruitment Cost	Holding +10 Stationed Siege Weapon Toughness +30% Stationed Siege Weapon Effectiveness Duchy +4 Fort Level Realm -30.00% Siege Weapon Maintenance -30.00% Siege Weapon Recruitment Cost	Holding +15 Stationed Siege Weapon Toughness +40% Stationed Siege Weapon Effectiveness Duchy +6 Fort Level Realm -45.00% Siege Weapon Maintenance -45.00% Siege Weapon Recruitment Cost	Burhs innovation for level 1  Castle Baileys innovation for level 2  Royal Armory innovation for level 3	Dedicated siege works allow the ruler to field and maintain superior-quality siege weapons.
Tax Offices	Duchy +15% Holding Taxes	Duchy +20% Holding Taxes	Duchy +30% Holding Taxes	Manorialism innovation for level 1  Windmills innovation for level 2  Cranes innovation for level 3	Collecting money from the peasantry is a 'taxing' venture. By assigning offices to a cohort of tax-collecting officials, we are sure to get what's due!
Royal Gardens	Duchy +5 Popular Opinion Holding +0.8 Monthly Tax Realm +5% Monthly Prestige -10% Stress Gain +4 Court Grandeur	Duchy +10 Popular Opinion Holding +1.1 Monthly Tax Realm +10% Monthly Prestige -20% Stress Gain +8 Court Grandeur	Duchy +15 Popular Opinion Holding +1.4 Monthly Tax Realm +15% Monthly Prestige -30% Stress Gain +12 Court Grandeur	Garden Architects tradition  Manorialism innovation for level 1  Windmills innovation for level 2  Cranes innovation for level 3	Few places allow people to relax and socialize as well as a beautiful garden. While a small and personal garden would suffice for most, only the most spectacular of creations is good enough for the wealthy and powerful!
Burial Site	Duchy +10% Control Growth +5 Popular Opinion +20 Plague Resistance Realm +0.3 Monthly Piety +2 Court Grandeur +20% Legend Spread Chance +10% Legitimacy Gain	Duchy +20% Control Growth +10 Popular Opinion +30 Plague Resistance Realm +0.5 Monthly Piety +4 Court Grandeur +30% Legend Spread Chance +15% Legitimacy Gain	Duchy +40% Control Growth +10 Popular Opinion +40 Plague Resistance Realm +1.0 Monthly Piety +6 Court Grandeur +40% Legend Spread Chance +20% Legitimacy Gain	Legends of the Dead DLC  Manorialism innovation for level 1  Windmills innovation for level 2  Cranes innovation for level 3	By creating a vast burial site for our dead, we will both keep miasma away from the populace and give a place of veneration and remembrance for our ancestors.

Faith duchy buildings

Faith duchy buildings can only be constructed if the barony owner's faith has the required doctrine or tenet.

Building type	Level 1 effects	Level 2 effects	Level 3 effects	Requirements	Description
Charnel Grounds	Duchy +5 Popular Opinion +10 Plague Resistance Realm +0.1 Monthly Piety -10% Stress Gain +5 Clergy Opinion	Duchy +10 Popular Opinion +15 Plague Resistance Realm +0.2 Monthly Piety -15% Stress Gain +10 Clergy Opinion Small Disease Resistance Health Boost	Duchy +15 Popular Opinion +20 Plague Resistance Realm +0.3 Monthly Piety -20% Stress Gain +15 Clergy Opinion Small Disease Resistance Health Boost	Sky Burials doctrine Independent or Liege's faith has Sky Burials	As much sites for spiritual cleansing as they are areas for the dead to rest, these open-air grounds provide a site for bodies to decompose.
Great Tower of Silence	Holding +50 Piety from Funerals +10 Legitimacy from Funerals Duchy +0.25 Monthly Control +10 Plague Resistance +30 Popular Opinion Realm +1 Monthly Piety +30% Legitimacy Gain +20% Legend Spread Chance +10 Same Faith Opinion +10 Zealot Vassal Opinion +20% Zealot Vassal Tax Contribution +20% Zealot Vassal Levy Contribution			Sky Burials doctrine Liege's faith has the Sky Burials doctrine	Our faith teaches us to dispose of the cadavers of righteous adherents by leaving them to animals and the open sky. Thusly the soul is kept pure and the community free from the corruption of decomposing flesh. When outsiders won't allow us our rites, we must build these towers to safeguard such mortal remains and symbolize our enduring belief.
Great Megalith	Holding +1.1 Monthly Tax Duchy +15% Development Growth +10 Popular Opinion Realm +0.2 Monthly Piety +5% Monthly Renown +10% Naval Speed +10% Monthly Learning Lifestyle Experience			Megalithic Constructions tenet	An extremely ambitious version of the Megalith, the Great Megalith project involves covering the landscape of the countryside in small Megalithic constructions centered around a single gargantuan construction.

Historical duchy buildings

Historical duchy buildings start already constructed. If so desired they can be replaced by other duchy buildings as well as rebuilt afterwards.

Building	Holding effects	County effects	Duchy effects	Barony	Description
Aurelian Walls	+3 Fort Level +50% Garrison Size -20 Danger +500 Garrison	+50% Hostile Raid Time +10% Development Growth +0.30 Monthly Development Growth	+15% Levy Size +15% Holding Taxes	Rome	The Aurelian Walls were built during the reign of the Roman Emperors Aurelian and Probus. To this day they provide formidable defense, completely enclosing the seven hills of Rome.
Theodosian Walls	+10.0 Monthly Tax +5 Fort Level +100% Garrison Size -20 Danger +1000 Garrison	+50% Hostile Raid Time +30% Levy Size +30% Holding Taxes +20% Development Growth +0.40 Monthly Development Growth	+15% Levy Size +15% Holding Taxes	Constantinople	The Theodosian Walls were built during the reign of Emperor Theodosius II in the early 5th century, but they still remain some of the most formidable fortifications built by human hands.