I've retrieved gliders from both a military airfield and prison
grounds.
I picked up a Kestrel 17 from China Lake. The pilot told me that he
called the tower and was denied permission to land. Once the pilot
declared an emergency, he was cleared to land by the tower - just in
time as he was 5 feet over the runway!
The Tehachapi Prison retrieve was a hassle but only because of the
soggy terrain. The prison sent a guard over to watch over us and he
kept us entertained with "prison" stories. Good thing the pilot landed
in some outlying land and not within the bad guy compound. I
memorialized this retrieve in a webpage:
Cu skies,
Steve AM