At Valle de los Caídos they only have general parking space. I doubt one would have any problems there because A) it's out in the middle of nowhere and B) because you have to pay to get in from the main road (unless you're Spanish and carrying the proper Spanish I.D. card).
In El Escorial, they do, I believe, have a few underground parking garages for which you have to pay but they're no more guarded than other parking lots. You take a card when you go in and you pay when you go out, either to a human or to a machine. But they do not have guards patrolling the lots, no. Parking around the Palace/Monastery is parking-meter-parking, by the way. We got ticketed in the few days AFTER these were installed, not being aware of the change.
Good luck! Saludos, MadridMan
_________________________
Visit BarcelonaMan.com for Barcelona information, Transportation, Lodging, & much MUCH more!
Curious about what could POSSIBLY be inside the brain of MadridMan? Visit
MadridMan's Madrid Blog