When to open borders?

[jedimogg]

i'm early into my first game and wondering what people's thoughts are about when to open borders and with who. all the AI's have offered and i'm not sure if i should. i know it can increase trade and allows missionaries, but does it make you vurnerable to attack? what have other's been doing?

 

[Panzer Ace]

If they have the same/close religion to you or you have good relations with them go ahead. But I'd keep a few 'border agents' there if you know what I mean...

 

[Sobsob]

I haven't played yet as I live in the uk but there is only going to be one way to see how the ai reacts and thats to try it.As I understand it open borders still keeps miltary units out though.

 

[tcjsavannah]

I opened them up only when I wanted to send my hindu missionaries in to convert their cities.

 

[Marcus_Aurelius]

The thing I hated most about Civ III was when people crossed my border and found a hole in my territory and plopped down (am I the only one that still shudders when I think I of that sound the Settlers make?) Consequently, my borders are permanently closed! Maybe when the memories are supressed I will open the borders again. As far as practical advice, I have none, since I am still waiting for my copy of Civ IV.