[vanilla] How do trade routes/roads/railroads/harbours work?

[NwabudikeMorgan]

No technologies affect any of these advantages, but as with roads, Trade Unions reduces upkeep by a third, to 1.44 gold a turn.

REducing 2 gpt by 1/3 gives 1.33, not 1.44

[Ran88dom99]

Very nice guide and analysis.

[timtrewyn]

This is a great article. Thank you!

I have experimented with the tactic of constructing road tiles to a new city one turn short of completion. Therefore I do not incur the maintenance cost until the road will pay off. As soon as the new city has enough population I can rapidly turn the partially constructed road into an operating road. I do not experience loss of accumulated construction in the time frames involved. Anyone else experiment with this?

[Lokos451]

Yeah, this is typically how I construct my roads, except that I'll typically also finish the roads in rough terrain to save worker turns, then they move back out into the flatlands to do the last turn on the road(s) there. It won't save you THAT much gold, but every little micro like this certainly adds up!

[llamapower]

so general question: when you guys are building roads, do you let the workers AI pick out the path or do you do it manually?

[weregamer]

I've had some unexpected and bad results when letting the AI do it. The AI will try to build the road using the regular movement pathing algorithm, which results in higher upkeep and slower travel when it goes around rough terrain instead of through it.

I'll only trust the AI for straight lines through clear terrain, or for two-tile stretches (from this tile to that adjacent tile).

[MadDjinn]

Originally Posted by llamapower

so general question: when you guys are building roads, do you let the workers AI pick out the path or do you do it manually?

Originally Posted by weregamer

I've had some unexpected and bad results when letting the AI do it. The AI will try to build the road using the regular movement pathing algorithm, which results in higher upkeep and slower travel when it goes around rough terrain instead of through it.

I'll only trust the AI for straight lines through clear terrain, or for two-tile stretches (from this tile to that adjacent tile).

I'd rather not trust the AI at all.

Sometime you want the connection both for the trade route and for a military roadway, but the 'auto' AI will go find another point on the road (same number or less tile distance) and build it from there, defeating the military side of the road usage.

There's also 'river side' issues, where I like having the road end up on both sides of a river (when going parallel to it) to allow for crossing the river easily. Sometimes the AI will pick a different path that leaves you on one side of the river only.

So yeah, build roads yourself if you need them to be in specific places.

[Brichals]

Originally Posted by MadDjinn

There's also 'river side' issues, where I like having the road end up on both sides of a river (when going parallel to it) to allow for crossing the river easily. Sometimes the AI will pick a different path that leaves you on one side of the river only.

Very good point that, saves you using movement points crossing rivers (after engineering is it?).

In addition.
Does anybody know how Arabias +1 effects trade routes. I get the feeling that it provides more than just 1 gpt per route. That is such a small amount.

[warlordtheft]

Also it allows you to save on roads and get them buil quicker. Dropping 4 workers in a line allows you to only to complete the road quicker and therfore start earning money from trade routes quicker.

[Ianwill93]

Does anybody know how Arabias +1effects trade routes. I get the feeling that it provides more than just 1 gpt per route. That is such a small amount.

It allows you to build a profitable trade route at lesser populations. What it does is effectively eliminate the -1 gpt modifier on the capital for all your trade routes, allowing you to build a profitable trade route faster.
This means that in the early game you can link a city to the capital quicker than usual and still be making money.
If you have a 6 pop capital, one 4 pop city, and 4 tiles of road between them, any normal civ will not be making money due to the -1 gpt. But Arabia should be making about 1gpt if im correct.
It allows for early Meritocracy while also being profitable.

[BuilderFTW]

Arabia's bonus might make the difference between making gold and loosing gold on an early trade route, but that does not change the fact that it is still a pitifully small amount of gold. If you want the early happiness from meritocracy, or need to move troops around, just build the road.

[Ianwill93]

True. But i guess if micromanagement mattered more in this game then the Arabians would have a good UA. But i usually just build the roads regardless.

[cain3456]

So I would get no benefit at all for connecting a road to a foreign capital? I tried it in the demo and didn't get any money for it.

[Veneke]

Unfortunately not cain3456. Trade routes can only be established between your own cities, not those of other Civs.

Your units would move faster to the enemy capital until you crossed their border though, that's a benefit of sorts.

[Calouste]

1) The 1 that Trade Unions provide on Harbours doesn't reduce Harbours' maintenance cost to 2, as that 1 is multiplied by Markets, Banks, Stock Exchanges, and in the case of the capital, the Commerce opener.

2) Monarchy:
The Tall Empire's answer to the Wide empire's answer to a Tall empire's high pop capital.

[Veneke]

You're quite right, it reduces it to at most 2 and even less under almost every circumstance. I've reworded the comment in parentheses accordingly.

[weregamer]

Reading the reworded parenthetical comment and around it, I saw something else you probably want to change.

"A harbor treats every water hex as a road" is correct but potentially misleading - you might want to add "including ice hexes".

I'm certain that I've had a harbor work on a city that was locked into a tiny sea by ice.

[Veneke]

That I didn't know. Honestly, I'm kinda surprised that trade routes can be formed across ice. Not that I think you're lying or anything but as I don't have a game to hand with this kind of scenario immediately to hand do you happen to have a screenshot or savegame handy to confirm?

[weregamer]

I'll try to chase one down - the frequency definitely depends on the map script. IIRC I saw this more when I was playing Terra/Small a lot.

[weregamer]

OK, I verified this a couple nights ago but it was on my ultrabook so I'm trying to figure out how to get the multi-meg file across. But it didn't take long to reproduce - washington on settler, small Terra, and a little scouting found me a site first try - just getting 2 settlers out (start was landlocked) and getting to Optics took most of the time.

On the turn after I rushed the harbor in the ice-bound city, I got the "trade route established" message and the income boost.

This city did have 2 tiles of open water next to it, and a third touching those, but ice blocked everything from there. I suppose if you had zero open water adjacent you *might* be prevented from building the harbor, but I doubt it.