[Tagging] How to map an artificial ground wall?

[Enrico Mattea]

Hi, thank you for your answer.
As can be seen in the picture, the complex has got an open entrance with 
a service road going through it. There isn't a real gate or barrier to 
stop vehicles, but from the very start of that road the area is private 
and military. Which way tags should I use to join the two surrounding 
walls so that I can properly tag the area as a whole (aeroway=aerodrome, 
name=* etc.)?
Thanks!
Ocirne