Forts, temples and laboratories

The three buildings of Dominions 6: fort levels and what each gives, how a fort draws in resources, and what temples and laboratories cost and unlock.

verified 6.37updated 2026-10-02 · Jake7 min read

A nation builds three kinds of structure in a province: a fort, a temple and a laboratory. They do different jobs. A fort turns a province into a collection point for resources and a depot for supply, and gives troops a place to shelter. A temple spreads faith. A laboratory is where mages do their research, forging and rituals. This page covers each in turn. How a siege against a fort plays out is on Siege, and is not repeated here.

The figures are the ones the manual states. We have not measured any of them.

The five fort levels

A fort is built in stages, and each stage is built on top of the one before. The manual’s table gives the cost in gold and the months for that stage alone, so going from nothing to a fortress means paying for the palisade first and then for the upgrade.

• Palisades: 1,000 gold, 5 months. Administration 15, no extra commander points, recruitment +50 percent, supply 150, wall integrity 200.
• Fortress: 600 gold, 3 months. Administration 30, +1 commander point, recruitment +75 percent, supply 750, wall integrity 500.
• Castle: 600 gold, 3 months. Administration 45, +1 commander point, recruitment +100 percent, supply 2,500, wall integrity 1,000.
• Citadel: 600 gold, 3 months. Administration 60, +2 commander points, recruitment +125 percent, supply 7,500, wall integrity 1,500.
• Grand citadel: 1,000 gold, 5 months. Administration 70, +2 commander points, recruitment +150 percent, supply 10,000, wall integrity 2,000.

The manual says outright that the attributes do not stack: a new level replaces the administration, recruitment, supply and wall integrity of the one beneath it. By our arithmetic, not the manual’s, the road to a castle costs 2,200 gold and 11 months in total, and to a citadel 2,800 gold and 14 months, assuming each stage is built in turn and the table’s figures hold.

The manual’s table has a column headed storage, and every row has one number too few for it. We read the last two figures in each row as supply and wall integrity, which matches the manual’s own siege example for supply. That reading is ours, and we do not know what storage is meant to show. The text of the manual never mentions storage.

Which levels a nation can build

The age of the game decides what most nations can build. The standard fort is the fortress in the early age, the castle in the middle age and the citadel in the late age. Some nations are limited to primitive forts, and some can build better than the standard for their era. The Nation Overview screen says which applies. A commander with the mason trait can build one level higher than his nation normally could. This is a trait of particular commanders, not of nations; the manual names Marignon and Ulm in the middle age as having such commanders. The grand citadel needs both a nation that can build a citadel and a mason.

The fort screen

A fort’s figures are shown when you click the Fortification button in the province screen, or press the f key. The fort’s commander points and recruitment bonus are added to the province’s own; see Province attributes for how the recruitment pool is worked out.

Administration

The fort’s administration value does three things.

• Collection from neighbours. It is the percentage of each adjacent province’s resources that the fort can draw in.
• Supply. It carries supply out to nearby provinces, up to four provinces away. The manual prints both a formula and a table of percentages by distance for this. They do not agree with each other or with the manual’s own example; Province attributes sets out the disagreement, so we do not restate it here.
• Income. It raises the income of the province the fort stands in by half the administration value as a percentage. The manual’s example is administration 30, giving 15 percent.

What a fort enables

• Full production. A province with no fort produces only half of its potential resources for its own use. A fort lifts it to the whole of that potential.
• Resources from neighbours. On top of that, the fort draws a share from each adjacent province. The share is taken from the neighbour’s whole potential, not from the half it would otherwise use. A palisade takes 15 percent and a fortress 30 percent. The manual’s worked example takes a province from 31 resources to 125 once a palisade stands in it.
• Limits on drawing. A land fort cannot draw from an adjacent sea province, nor a sea fort from land. A fort cannot draw from an adjacent province that has a fort of its own. No fort can draw from an adjacent enemy province. In the manual’s example a second palisade next door took 13 resources away from the first, which dropped from 125 to 112. A river does not stop the flow, because boats are enough.
• Recruitment. The recruitment bonus in the table raises the points a province has to spend. The manual’s table gives the bonus; it does not list which units need a fort.
• Shelter in a siege. The fort’s castle guards and wall defenders help defend it when it is stormed, and are restored for each fight, like ordinary province defence. The manual says their number depends on the fort level but does not give the numbers. See Siege.
• A link to home. Income needs a chain of friendly provinces reaching back to a fort. See Province attributes.

Temples

A temple helps a nation’s faith spread, either by adding checks to the spread of dominion or, for nations that sacrifice blood slaves, by being the place where the sacrifices are made. Mictlan in the early and late ages is the exception that gets no direct spread from temples. A temple also gives priests a bonus when they preach.

• Where. Only in a province you hold, and only one per province. If an enemy captures the province, the temple is destroyed at once, and the capture report says so.
• Cost. 600 gold as standard. Man and Marverni pay half. Pangaea pays half in a forest province. Gath in the late age pays double everywhere. The manual gives no build time for a temple.
• What it does. Pressing the Temple button reports your dominion spread for the turn and its odds of success, expressed as checks per month. Every temple makes checks, and so do the pretender, the prophet and the home province. How those checks work, how temples lift the dominion ceiling and how they help preaching is on Dominion, under the temple check entry.

Laboratories

A laboratory is the last of the three. The manual calls it a collection point for magic gems and a centre of research. Without one in the province:

• a mage cannot use the Research order, which is covered on Research;
• gems cannot be moved from the national inventory to a mage;
• a ritual cannot be cast. See Rituals;
• a mage cannot Forge Item. See Forging;
• the gems of a magic site reach you only if friendly land links the site to a province with a laboratory. See How magic sites work.

A laboratory costs 600 gold. Some nations pay less: the manual names Arcoscephale, and says Pangaea pays half in a forest province. The manual gives no build time for laboratories, and does not say whether a laboratory finished this turn can host this turn’s rituals; the Rituals page notes that labs are built later in the turn than rituals are cast.

What the manual leaves open

• What the storage column of the fort table shows.
• The number and type of castle guards and wall defenders at each fort level.
• Which commanders and troops need a fort to be recruited, as opposed to the recruitment bonus the fort gives.
• Build times for temples and laboratories.
• The cost of each nation’s temple and lab beyond the exceptions named above.