Why do I have the OPen Borders boost to Tourism with some cive but not others?

[Barking Iguana]

I have mutual Open Borders Agreements with civs on my continent and civs on others. But I'm only getting the boost on my continent. Is there a tech requirement to get it across oceans? I have Astronomy, but not Navigation.

Also, I take it the agreements don't have to be mutual, but I see different threads saying opposite things about which may is required.

 

[Browd]

There is no overseas limitation on open borders, but you need to be mindful of the "direction" of the open borders treaty you have.

To get the tourism boost vs. another civ, you need the other civ's open borders (i.e., their border are open to your units). You do not have to "give" open borders to get the benefit. In fact, if you only give open borders (i.e., your borders are open to him, but his are not open to you), he gets the tourism boost and you do not.

 

[Barking Iguana]

Thank you. That is what I had thought, but I got confused because I was looking at a neighbor's tourism rather than my own.