[SI_Rob]

I misread the OP as NASA, which was careless but I still think the observation is worth noting. Also worth noting is that there is a museum on the NSA campus (National Cryptologic Museum) that anyone can visit without any clearance, and though there are vastly trickier chicanes to contend with compared to the access at NASA administrative HQ, merely visiting the cryptologic museum ushers one past several otherwise highly restricted perimeter zones.