Have you seen the Great Wall of Cabin John?
Here is a recent street view of the walled compound that is the Cabin John Middle School now under construction in Potomac, on a parcel larger than Rock Creek Hills Park, with uneven topography (sound familiar?) requiring construction of massive retaining walls to achieve adequate flat acreage (for parking lots, loading docks, service drives, etc.):
[click image for larger version]
Isn't that something? The school yard winds up at the roof level of the homes across the street. And don't forget the safety fence needed atop the retaining wall... What's that, an eight foot fence atop an eleven foot wall?
Here's the aerial view:
Do you want to see a walled compound replace Rock Creek Hills Park?