How overseas trading works

[PrinceBimz]

Got this from the CIV3 site in the FAQs. There are a few things here I never did know, such as the coast based trading. So I am posting this here in case anyone else did not know or for any newbies...

How does overseas trading work?
There are two ways to establish a trade route between two cities on different continents, or in situations where roads or railroads cannot link two cities in any way: airports and harbors.

Using airports, both cities need only have airports to enable trade.

To trade via harbors, both cities need not only have harbors, but there must also be an unblocked path of navigable tiles between the two cities. This means that if your current research level (i.e., before Astronomy) restricts your naval vessels from leaving coast tiles, only coast-based trade routes can be established. Finally, rival vessels can block this route, preventing naval trade between two cities.

[Stuie]

That coastal trading thing is very important. I've gained a bad reputation from early trading where my route gets cut off suddenly by stumbling into a war, and my enemy's galley blocks the coastal route. The AI Civs view that as breaking a 20-turn deal. Becuase of that, I try not to make any overseas deals until I have Astronomy.

[G'Kar]

rival vessels can block this route, preventing naval trade between two cities.

That's a trick I've never attempted to pull (just blocking coastal tiles in the early game). I'll try to use it next game if only for the sake of destroying AI reps and hurting AI-AI trade.

[PrinceBimz]

All of this time I never knew that about the coastal trade. Its certainly is good to know, especially being able to block an early AI trade route. In addition if that happens to me I will know what the problem is. I have done other naval blockades before, not coastal but in a channel or narrow waterway that cut off AI overseas trading. This was later during the game and navies were modern using destroyers and such. These make good blockade vessels because they build faster then battleships.

[Theseus]

Clarification: You do not necessarily need to blockade a coastal route with ships. Pre-Astro, just declaring war on one of the two civs involved in such a coastal trade can block, if YOUR coast is part of the route.

[Vlado]

Btw, it's really no use to break AI-AI 20 turn deals to give them rep hits since they don't get a rep hit that affect further AI-AI trade.

[Ragnar_84]

I was actually able to gain luxury benefits on different continents without a harbor/airport on the one without luxuries but they were connected by coastal squares. I was in the process of building a harbor and was stunned when I saw my cities with luxury benefits.

[Stuie]

Originally posted by Ragnar_84
I was actually able to gain luxury benefits on different continents without a harbor/airport on the one without luxuries but they were connected by coastal squares. I was in the process of building a harbor and was stunned when I saw my cities with luxury benefits.

If your road network is connected to a Civ with which you are not at war and they have a harbour, trade will flow through their territory into yours. This makes trade ridiculously easy and blockades almost impossible once you research navigation. Which gives me an idea.... maybe I'll try moving trade over ocean squares to a later tech. That would allow the age of sail to be a little more intense.

[Datajack Franit]

Maybe you should just seize the other civ's harbor and that's how you block their commerce

[Paddy]

yeah... then leave their cities in ruins...

[Shogun Gunner]

Originally posted by Stuie
That coastal trading thing is very important. I've gained a bad reputation from early trading where my route gets cut off suddenly by stumbling into a war, and my enemy's galley blocks the coastal route. The AI Civs view that as breaking a 20-turn deal. Becuase of that, I try not to make any overseas deals until I have Astronomy.

Well that explains things! I had this situation exactly as you described! I couldn't figure out why that fat German bastard was pissed at me.

How exactly was the enemy's galley blocking the coast route, by parking in front of the port city?

[Shogun Gunner]

Originally posted by Vlado
Btw, it's really no use to break AI-AI 20 turn deals to give them rep hits since they don't get a rep hit that affect further AI-AI trade.

Is this for real? How do you know this? Not doubting you, just asking for additional information.

[pedrojedi]

Well, that must affect something, or it would be much more difficult to pull a diplomatic victory.

[ceroomaster]

Originally posted by Stuie
Which gives me an idea.... maybe I'll try moving trade over ocean squares to a later tech. That would allow the age of sail to be a little more intense.

I do this. I have sea squares on Navigation, and usually push ocean squares back to at least the age of steam kicks in...

[MrWhereItsAt]

Further clarification: your sea trade routes aren;t just cut by enemy territory/ships, but if a Barbarian Galley appears in the middle of the only route your trade route goes down too. You can be at peace with everyone and still have your trade route cut off by Barbs - often leading to wars.