The North and South divider is a military base with this big Mexican flag and these  two weird looking towers. There is also a time zone here.  El Norte follows  Pacific time like California and El Sur follows Mountain times.

I did try to match the dark green color of the perimeter wall across the road. Next time I'm down there, I'll ask them for a paint sample and probably based on the flag incident (see text across photo) end up in jail for trying to obtain highly classified info...

We were told that we had to take this photo from that side only, (?) after the officer in charge went inside to ask the base commander for permission to let me photograph the  big Mex. flag on top of their fortress.