Computed · Crusader Kings III 1.20.0.3

Best duchy buildings

Crusader Kings III duchy capital buildings ranked by goal (development, army, levies, income, opinion) from their top level's effects, with total gold cost.

Computed ranking

A chain is judged by its last level and the gold for all its levels. Effects that only apply under a condition (a culture, terrain or government) are left out. Payback = gold for all levels ÷ (the top level's flat monthly tax × 12), in years. Percentage tax bonuses depend on the holding's own tax and are not counted, so the true payback is shorter.

Each effect is the game's own modifier line, taken as positive when the game colours it green. A list holds everything with at least one positive effect of that kind, the ones with the most such effects first; "Largest …" boxes rank the values of one modifier against each other (same modifier, same unit).

Read from the game files of Crusader Kings III 1.20.0.3: common/buildings. Base values: no culture, faith, era, terrain or character modifiers unless a line says so.

Tax buildings by payback time


The Theodosian Walls	1	3,000	10	25
Great Megalith	1	485	1.10	36.70
Dragon Kiln	3	2,310	2	96.30
Royal Gardens	3	2,310	1.40	137.50
Royal Reserves	3	2,310	1.40	137.50
Charnel Grounds	3	2,310	1.10	175

Best duchy buildings for development

7 duchy buildings with at least one positive development effect, the ones with the most such effects first.

duchy building	Effects	What it gives
The Aurelian Walls1 level, 3,000 gold in all	2	Development Growth +0.3/month (County) Development Growth +10% (County)
The Theodosian Walls1 level, 3,000 gold in all	2	Development Growth +0.4/month (County) Development Growth +20% (County)
Charnel Grounds3 levels, 2,310 gold in all	1	Development Growth +30% (Each de jure county of the duchy)
Dragon Kiln3 levels, 2,310 gold in all	1	Character capital county monthly development growth +0.6/month (Holder)
Examination Hall3 levels, 2,310 gold in all	1	Development Growth +30% (Each de jure county of the duchy)
Great Megalith1 level, 485 gold in all	1	Development Growth +15% (Each de jure county of the duchy)
Royal Reserves3 levels, 2,310 gold in all	1	Development Growth +30% (Each de jure county of the duchy)

Largest Development Growth

1.Charnel Grounds · Each de jure county of the duchy+30%
2.Examination Hall · Each de jure county of the duchy+30%
3.Royal Reserves · Each de jure county of the duchy+30%
4.The Theodosian Walls · County+20%
5.Great Megalith · Each de jure county of the duchy+15%
6.The Aurelian Walls · County+10%

Best duchy buildings for tax, income & construction

10 duchy buildings with at least one positive tax, income & construction effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Marches3 levels, 2,310 gold in all	3	Holding Taxes in Mountains +30% (Each de jure county of the duchy) Holding Taxes in Desert Mountains +30% (Each de jure county of the duchy) Holding Taxes in Hills +30% (Each de jure county of the duchy)
The Theodosian Walls1 level, 3,000 gold in all	3	Holding Taxes +15% (Each de jure county of the duchy) Tax +10/month (Province) Holding Taxes +30% (County)
Charnel Grounds3 levels, 2,310 gold in all	1	Tax +1.1/month (Province)
Dragon Kiln3 levels, 2,310 gold in all	1	Tax +2/month (Province)
Great Megalith1 level, 485 gold in all	1	Tax +1.1/month (Province)
Great Tower of Silence1 level, 1,100 gold in all	1	Zealot Vassal Tax Contribution +20% (Holder)
Royal Gardens3 levels, 2,310 gold in all	1	Tax +1.4/month (Province)
Royal Reserves3 levels, 2,310 gold in all	1	Tax +1.4/month (Province)
Tax Offices3 levels, 2,310 gold in all	1	Holding Taxes +30% (Each de jure county of the duchy)
The Aurelian Walls1 level, 3,000 gold in all	1	Holding Taxes +15% (Each de jure county of the duchy)

Largest Tax

1.The Theodosian Walls · Province+10/month
2.Dragon Kiln · Province+2/month
3.Royal Gardens · Province+1.4/month
4.Royal Reserves · Province+1.4/month
5.Charnel Grounds · Province+1.1/month
6.Great Megalith · Province+1.1/month

Largest Holding Taxes

1.Tax Offices · Each de jure county of the duchy+30%
2.The Theodosian Walls · County+30%
3.The Aurelian Walls · Each de jure county of the duchy+15%
4.The Theodosian Walls · Each de jure county of the duchy+15%

Best duchy buildings for levies & garrison

6 duchy buildings with at least one positive levies & garrison effect, the ones with the most such effects first.

duchy building	Effects	What it gives
The Theodosian Walls1 level, 3,000 gold in all	3	Levy Size +15% (Each de jure county of the duchy) Garrison Size +100% (Province) Levy Size +30% (County)
Marches3 levels, 2,310 gold in all	2	Levy Reinforcement Rate +100% (Each de jure county of the duchy) Garrison Size +100% (Each de jure county of the duchy)
The Aurelian Walls1 level, 3,000 gold in all	2	Levy Size +15% (Each de jure county of the duchy) Garrison Size +50% (Province)
Great Barracks1 level, 350 gold in all	1	Garrison Size +150% (Each de jure county of the duchy)
Great Tower of Silence1 level, 1,100 gold in all	1	Zealot Vassal Levy Contribution +20% (Holder)
Royal Armories3 levels, 2,310 gold in all	1	Levy Size +40% (Each de jure county of the duchy)

Largest Levy Size

1.Royal Armories · Each de jure county of the duchy+40%
2.The Theodosian Walls · County+30%
3.The Aurelian Walls · Each de jure county of the duchy+15%
4.The Theodosian Walls · Each de jure county of the duchy+15%

Largest Garrison Size

1.Great Barracks · Each de jure county of the duchy+150%
2.Marches · Each de jure county of the duchy+100%
3.The Theodosian Walls · Province+100%
4.The Aurelian Walls · Province+50%

Best duchy buildings for men-at-arms & knights

7 duchy buildings with at least one positive men-at-arms & knights effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Jousting Grounds3 levels, 2,310 gold in all	15	Men-at-Arms Maintenance -10% (Holder) Stationed Heavy Cavalry Damage +60% (Province) Stationed Heavy Cavalry Toughness +60% (Province) Stationed Heavy Cavalry Screen +60% (Province) Stationed Heavy Cavalry Pursuit +60% (Province) Stationed Light Cavalry Damage +40% (Province) Stationed Light Cavalry Toughness +40% (Province) Stationed Light Cavalry Screen +40% (Province) Stationed Light Cavalry Pursuit +40% (Province) Stationed Elephant Cavalry Damage +60% (Province) Stationed Elephant Cavalry Toughness +60% (Province) Stationed Camel Cavalry Damage +40% (Province) Stationed Camel Cavalry Toughness +40% (Province) Stationed Camel Cavalry Screen +40% (Province) Stationed Camel Cavalry Pursuit +40% (Province)
Archery Grounds3 levels, 2,310 gold in all	11	Men-at-Arms Maintenance -10% (Holder) Stationed Archers Damage +60% (Province) Stationed Archers Toughness +15% (Province) Stationed Skirmishers Screen +40% (Province) Stationed Skirmishers Damage +60% (Province) Stationed Skirmishers Toughness +40% (Province) Stationed Skirmishers Pursuit +40% (Province) Stationed Archer Cavalry Screen +40% (Province) Stationed Archer Cavalry Damage +40% (Province) Stationed Archer Cavalry Toughness +15% (Province) Stationed Archer Cavalry Pursuit +40% (Province)
Crown Smithies3 levels, 2,310 gold in all	5	Men-at-Arms Maintenance -10% (Holder) Stationed Spearmen Damage +25% (Province) Stationed Spearmen Toughness +60% (Province) Stationed Heavy Infantry Damage +25% (Province) Stationed Heavy Infantry Toughness +60% (Province)
Military Academies3 levels, 2,310 gold in all	5	Number of Knights +6 (Holder) Knight Effectiveness +75% (Holder) Army Gold Maintenance -5% (Holder) Men-at-Arms Recruitment Cost -30% (Holder) Size of Men-at-Arms Regiments +3 (Holder)
Great Barracks1 level, 350 gold in all	4	Size of Title Men-at-Arms Regiments +1 (Holder) Max Title Men-at-Arms Regiments +1 (Holder) Men-at-Arms Recruitment Cost -10% (Holder) Men-at-Arms Maintenance -12% (Holder)
Siege Works3 levels, 2,310 gold in all	4	Siege Weapon Recruitment Cost -45% (Holder) Siege Weapon Maintenance -45% (Holder) Stationed Siege Weapon Effectiveness +40% (Province) Stationed Siege Weapon Toughness +15 (Province)
Royal Armories3 levels, 2,310 gold in all	3	Army Gold Maintenance -10% (Holder) Stationed Men-at-Arms Damage +25% (Province) Stationed Men-at-Arms Toughness +25% (Province)

Largest Men-at-Arms Maintenance

1.Great Barracks · Holder-12%
2.Archery Grounds · Holder-10%
3.Crown Smithies · Holder-10%
4.Jousting Grounds · Holder-10%

Best duchy buildings for warfare: advantage, supply & movement

6 duchy buildings with at least one positive warfare: advantage, supply & movement effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Siege Works3 levels, 2,310 gold in all	5	Siege Weapon Recruitment Cost -45% (Holder) Siege Weapon Maintenance -45% (Holder) Stationed Siege Weapon Effectiveness +40% (Province) Stationed Siege Weapon Toughness +15 (Province) Additional fort level +6 (Each de jure county of the duchy)
Great Barracks1 level, 350 gold in all	4	Supply Limit +100% (Each de jure county of the duchy) Hostile Raid Time +50% (Each de jure county of the duchy) Defender Holding Advantage +15 (Each de jure county of the duchy) Additional fort level +6 (Each de jure county of the duchy)
Marches3 levels, 2,310 gold in all	4	Supply Limit +100% (Each de jure county of the duchy) Hostile Raid Time +75% (Each de jure county of the duchy) Defender Holding Advantage +15 (Each de jure county of the duchy) Additional fort level +6 (Each de jure county of the duchy)
The Aurelian Walls1 level, 3,000 gold in all	2	Hostile Raid Time +50% (County) Fort Level +3 (Province)
The Theodosian Walls1 level, 3,000 gold in all	2	Fort Level +5 (Province) Hostile Raid Time +50% (County)
Great Megalith1 level, 485 gold in all	1	Naval Speed +10% (Holder)

Largest Hostile Raid Time

1.Marches · Each de jure county of the duchy+75%
2.Great Barracks · Each de jure county of the duchy+50%
3.The Aurelian Walls · County+50%
4.The Theodosian Walls · County+50%

Largest Additional fort level

1.Great Barracks · Each de jure county of the duchy+6
2.Marches · Each de jure county of the duchy+6
3.Siege Works · Each de jure county of the duchy+6

Best duchy buildings for prestige & piety

6 duchy buildings with at least one positive prestige & piety effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Great Megalith1 level, 485 gold in all	2	Piety +0.25/month (Holder) Monthly Renown +5% (Holder)
Burial Site3 levels, 2,310 gold in all	1	Piety +1/month (Holder)
Charnel Grounds3 levels, 2,310 gold in all	1	Piety +1/month (Holder)
Great Tower of Silence1 level, 1,100 gold in all	1	Piety +1/month (Holder)
Leisure Palaces3 levels, 2,310 gold in all	1	Monthly Prestige +15% (Holder)
Royal Gardens3 levels, 2,310 gold in all	1	Monthly Prestige +15% (Holder)

Largest Piety

1.Burial Site · Holder+1/month
2.Charnel Grounds · Holder+1/month
3.Great Tower of Silence · Holder+1/month
4.Great Megalith · Holder+0.25/month

Best duchy buildings for opinion, control & legitimacy

8 duchy buildings with at least one positive opinion, control & legitimacy effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Great Tower of Silence1 level, 1,100 gold in all	5	Same Faith Opinion +10 (Holder) Zealot Vassal Opinion +10 (Holder) Legitimacy Gain +30% (Holder) Popular Opinion +30 (Each de jure county of the duchy) Monthly county control growth +0.25/month (Each de jure county of the duchy)
Burial Site3 levels, 2,310 gold in all	3	Legitimacy Gain +20% (Holder) Popular Opinion +10 (Each de jure county of the duchy) Control Growth +40% (Each de jure county of the duchy)
Charnel Grounds3 levels, 2,310 gold in all	3	Popular Opinion +15 (Each de jure county of the duchy) Clergy Opinion +15 (Holder) Legitimacy Gain +20% (Holder)
Leisure Palaces3 levels, 2,310 gold in all	2	Control Growth +60% (Each de jure county of the duchy) Monthly county control growth +0.4/month (Each de jure county of the duchy)
Great Barracks1 level, 350 gold in all	1	Monthly county control growth +0.2/month (Each de jure county of the duchy)
Great Megalith1 level, 485 gold in all	1	Popular Opinion +10 (Each de jure county of the duchy)
Royal Gardens3 levels, 2,310 gold in all	1	Popular Opinion +15 (Each de jure county of the duchy)
Royal Reserves3 levels, 2,310 gold in all	1	Popular Opinion +15 (Each de jure county of the duchy)

Largest Popular Opinion

1.Great Tower of Silence · Each de jure county of the duchy+30
2.Charnel Grounds · Each de jure county of the duchy+15
3.Royal Gardens · Each de jure county of the duchy+15
4.Royal Reserves · Each de jure county of the duchy+15
5.Burial Site · Each de jure county of the duchy+10
6.Great Megalith · Each de jure county of the duchy+10

Largest Legitimacy Gain

1.Great Tower of Silence · Holder+30%
2.Burial Site · Holder+20%
3.Charnel Grounds · Holder+20%

Largest Monthly county control growth

1.Leisure Palaces · Each de jure county of the duchy+0.4/month
2.Great Tower of Silence · Each de jure county of the duchy+0.25/month
3.Great Barracks · Each de jure county of the duchy+0.2/month

Best duchy buildings for skills & lifestyle experience

2 duchy buildings with at least one positive skills & lifestyle experience effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Examination Hall3 levels, 2,310 gold in all	1	Monthly Lifestyle Experience +12% (Holder)
Great Megalith1 level, 485 gold in all	1	Monthly Learning Lifestyle Experience +10% (Holder)

Best duchy buildings for health, stress & bloodline

5 duchy buildings with at least one positive health, stress & bloodline effect, the ones with the most such effects first.

duchy building	Effects	What it gives
Charnel Grounds3 levels, 2,310 gold in all	2	Plague Resistance +40 (Each de jure county of the duchy) Stress Gain -20% (Holder)
Burial Site3 levels, 2,310 gold in all	1	Plague Resistance +40 (Each de jure county of the duchy)
Great Tower of Silence1 level, 1,100 gold in all	1	Plague Resistance +10 (Each de jure county of the duchy)
Leisure Palaces3 levels, 2,310 gold in all	1	Stress Loss +35% (Holder)
Royal Gardens3 levels, 2,310 gold in all	1	Stress Gain -30% (Holder)

Largest Plague Resistance

1.Burial Site · Each de jure county of the duchy+40
2.Charnel Grounds · Each de jure county of the duchy+40
3.Great Tower of Silence · Each de jure county of the duchy+10