Does signing a 2 way open borders agreement with AI increase trade income?

Are there any benefits other than a right of passage?

Don't think so. Lets my Triremes get around their cities so I can find other CSs

Are there any benefits other than a right of passage?

Not really but a right of passage is pretty big.

For trade, no. But it depends on what kind of victory you're going for. If you're going for Domination, you need Open Borders to scout, but it's also an invitation to be mapped out yourself. For all other victories, you don't need open borders at all since nearly all city states are accessible from the sea; you just may have to go an extra tile or two around the other civs to find them, that's all.

There's no diplomatic hit for constantly refusing two-way open borders agreements. Being friendly with other civs is a mug's game, but if you insist on trying you get better results with pacts of cooperation with strong civs and pacts of secrecy with them against weaker civs.

In short, you may as well refuse all two way open borders agreements UNLESS you are determined to go for a domination victory and don't mind the risk.

Don't get me even started. CIV4 beats this game in these aspects like 1.000 to 1.

Err .. does selling open borders count?

well, only one extremely rare thin.

If part of your empire connected by road/ water tie that belong to other civ, then in order to get it connected to trade NW you need open borders.

well, only one extremely rare thin.

If part of your empire connected by road/ water tie that belong to other civ, then in order to get it connected to trade NW you need open borders.

In my current game I took out Catherine and Darious(?) early in the game while leaving Washington who was way off on the western edge of the continent. The conquered cities were a ways away from mine.

Eventually because it seems the AI can build all the cities it wants he started putting them between my far away cities and my capitol. Every 90 turns or so my trade links would be broken and then Georgie Boy would pop up asking for open borders. It seems he does not like losing the cash from broken trade routes either. Once I agreed to open borders my cash flow would turn positive again in the next turn. So if you are intertwined with an empire you have not wiped out yet, you may need open borders just for the extra cash and access.

I try not to sign two-way open borders agreements, since the AI likes to attack you after scouting your territory and finding your cities undefended.

Instead, I always buy open borders from the AI if I need it. The AI gives it away for like 50 gold, even in the modern age, which is dirt cheap.

Enemy cultural border will stop your trade routes. I guess open borders would help with this... but I've had some strange results with trade routes. I've had situations where I had to ally/befriend city states to finish the trade routes, but sometimes I can't get the railroad bonus to work and sometimes I get warnings the trade routes are broken even when they are not...

Don't get me even started. CIV4 beats this game in these aspects like 1.000 to 1.

Wow, 1-to-1, eh? That's quite a ratio.

Wow, 1-to-1, eh? That's quite a ratio.
Haha! :lol: I'm assuming you know that many countries use commas as decimal points and dots as thousands separators? :mischief:

I'm not even convinced that open borders improves your relations in the long term. I've certainly managed to get defensive pacts without giving open borders to any opponent all game long. Whenever anything offends an AI, such as they settle next to you, they cancel every agreement whether you've got open borders or not.

Actually the AI back-stabbed me once with open border. They moved all their army into my places and then DOW on me! After that I reject all the two-way open borders except for the really weak civs.