Being able to build city districts in Civilization VI as quickly as possible gives a clear advantage in the game. Thanks to the work of the great minds over at the CivFanatics forum, the mechanics behind the construction of districts have been unearthed.
One of the more obscure mechanics in Firaxis' Civilization VI is the one governing the time to build city districts. It's obscure enough that even players who can regularly win at the highest difficulty levels of the game often remain largely ignorant of it.
The careful placement of city districts to get maximum bonuses and coverage across your empire is the key to the game. Get that construction mosaic right, and the rest of the game falls into place. Well, provided you don't spawn next to Alexander the Great and all your tiles are food and no production. There's only one button that's the cure for that and it's called Restart.
Provided that isn't the case - here's a simple explanation of the mathematics behind City District construction, and how to get a 40 per cent faster build time for them.
Add up the number of districts you have completed, then divide this number by the number of districts you have actually researched. If the answer is below one then you will not receive a discount.
For example: You want to build an Encampment District. You have already built one. You have researched Astrology to unlock Holy Sites, and Writing to unlock the Campus District. You have one Holy Site built, and one Campus. This gives you three districts researched divided by three districts built. 3 ÷ 3 = 1. You're going to get a 40 per cent discount on your next Encampment.
You can also simply look at the Production screen for your city. If the construction time for one type of district is less than for another - you're getting a discount.
Note: The Government Plaza only receives a 25 per cent discount, as you can build only one. Districts that fall into the General category - Aqueduct, Dam, Spaceport, Neighbourhood and the City Centre - are not eligible to receive a discount. Districts unique to a particular Civ - the Zulu Ikanda for example - get the same discount according to the rules above as the district they replace.
- You need to have built as many Districts as you have researched.
- Your total number of Districts is greater than than total number of placed/built Districts of the type you wish to build next, then you are eligible for a discount.
- Capturing a city with Districts you have not yet researched does not alter the ability to gain a discount.
- The cost of producing a District is locked as soon as you place it. It does not alter.
- Governors that have the ability to purchase a District (Moksha with Faith, Reyna with Gold) use the discount, provided the District is not already under construction when their perk takes effect. Liang's 20 per cent discount ability and the Pantheon effect City Patron Goddess are also applied in the same way.
Gaining discounts for Districts is a balancing act. To gain the most from the discounts requires thinking carefully about what you research and when. The situations the game sometimes forces you into can derail even the best plans. See Alexander the Great above! Some Districts are easier to avoid researching - such as Harbours - because of the way the Tech Tree is structured.
For instance, Iron Working is important in the early game - you want to know where those Iron resources are located on the map. However, researching it unlocks Encampment, and that adds to your Districts Researched metric - which is a factor in calculating whether you are eligible for a discount, on, for example, a Campus District.
Consequently, the best method to exploit discounts is to decide which type of District you are going to build a number of. So, for instance, constructing two or three Campus Districts at full cost as soon as you are able - while avoiding researching another type of District - means you are setting yourself up to gain discounts on a number of subsequent different Districts.
Obviously population is another factor in being able to construct Districts - so ensuring there is adequate food supply to ensure growth is vital.
So while attempting to get District discounts is a valid and useful strategy, it must be noted that flexibility in any strategy is important in Civilization VI. That is to say, if delaying research on a particular tech to gain the discount means you are at the mercy of an aggressive neighbour, then clearly it's the wrong strategy.
We'd like to thank the Big Brains over at https://www.civfanatics.com for crunching the data on this one. And it's fascinating to think that even after the game has been out this long, players - and good players too - are still discovering some of the mechanics behind it.