What gives the free walls in every city

[danhynes]

Does anyone know offhand which tech or cultural builds the free city walls in every city. I tend to notice it mid/late game but forget to look for it.

 

[smartcanuck1988]

Civil Engineering (Civic) I think

 

[Sagax]

Civil Engineering I think

It definitely is Civil Engineering.

 

[JosephC]

I think what your talking about is Urban Defenses from the Civil Engineering Civic.

Urban Defenses: Gives all of your cities an automatic 200 Fortification Strength and the ability to bombard.

 

[danhynes]

Yes you are both right thanks