How do Trade Routes work?

[Archaelicos]

I'm curious how the trade route system works. I know it's automatic but how does the system pick which cities it develops trade routes with? When you pick up a tech like currency, does every city just automatically get a new trade route, or do they take some time to fill out and "grow up." Are the values of trade routes a function of city size and distance? Do trade routes provide GOLD or COMMERCE?

Thanks!

 

[MrCynical]

how does the system pick which cities it develops trade routes with?

It simply picks the most profitable trade routes (and so connects to the largest cities, adjuting for which civ they belong to, whether they're on a different continent, etc.)

When you pick up a tech like currency, does every city just automatically get a new trade route, or do they take some time to fill out and "grow up

The new trade routes are added immediately you get currency.

Are the values of trade routes a function of city size and distance?

Yes, though they also adjust based on whether they are foreign or domestic, and whether they're intercontinental.

Do trade routes provide GOLD or COMMERCE?

Trade routes give commerce.

 

[Archaelicos]

Great, clear answers. Thank you! Are there formulas for how many trade routes you get? E.g., you get 1 + 1 more per 3 population or something? What is the ordering of route values?

Is it, lowest to highest: domestic, foreign, domestic intercontinental, foreign intercontinental?

How does it calculate the most profitable route? Do you have to find cities that have capacity for routes, and can you lose routes if another, more profitable route crops up for one of the cities you have a route with?

 

[magicalsushi]

The number of trade routes is completely independent of the city's population. It only depends on which technologies, civics and buildings you have. All cities get 1, then they get 1 more for having Currency, 1 more for having Corporation (as in the technology, not actual corporations), 1 more for having a castle (prior to Economics), 1 more for having an airport, 1 more for running Free Market and 2 more for coastal cities if you have the Great Lighthouse. Because Economics obsoletes the castle and Great Lighthouse, the maximum number of trade routes in a city is 5 (or 6 if you can get an airport before you research Economics - is that possible?).

Population does not affect the number of trade routes, but it may affect their values. I'm not sure whether it does.

 

[Archaelicos]

Ahhhhh, ok. So that really does make currency huge, you basically double your trade routes.

 

[MrCynical]

The number of trade routes is completely independent of the city's population. It only depends on which technologies, civics and buildings you have. All cities get 1, then they get 1 more for having Currency, 1 more for having Corporation (as in the technology, not actual corporations), 1 more for having a castle (prior to Economics), 1 more for having an airport, 1 more for running Free Market and 2 more for coastal cities if you have the Great Lighthouse. Because Economics obsoletes the castle and Great Lighthouse, the maximum number of trade routes in a city is 5 (or 6 if you can get an airport before you research Economics - is that possible?).

You can also get one extra trade route if you pass the single currency resolution with the UN. I'm not sure if it's possible to get flight without economics, but it's implausible in game terms anyway.

 

[magicalsushi]

Ahhhhh, ok. So that really does make currency huge, you basically double your trade routes.

AND you can build markets, AND you can produce gold from hammers, AND you can sell technology for gold...I love it to bits, it opens up virtually every important method of keeping your economy afloat! I usually beeline for it straight after Alphabet, mostly for the trade routes.

Archaelicos, that's a good point about the single currency resolution. I kept feeling like I was missing something.

 

[volfan37132]

I don't think this has been mentioned yet. Forgive me if it has.

You must have an open borders agreement with a foreign civ
to have trade routes with that specific civ.

 

[onedreamer]

The number of trade routes is completely independent of the city's population. It only depends on which technologies, civics and buildings you have. All cities get 1, then they get 1 more for having Currency, 1 more for having Corporation (as in the technology, not actual corporations), 1 more for having a castle (prior to Economics), 1 more for having an airport, 1 more for running Free Market and 2 more for coastal cities if you have the Great Lighthouse. Because Economics obsoletes the castle and Great Lighthouse, the maximum number of trade routes in a city is 5 (or 6 if you can get an airport before you research Economics - is that possible?).

Population does not affect the number of trade routes, but it may affect their values. I'm not sure whether it does.

You can have 6 if you play the Carthaginians and own the Great Lighthouse. After Corporation and the Flight you can have 6 again (1 base, 1 currency, 1 corporation, 1 free market, 1 airport, 1 cothon).