Hi Mike,
The pictures were taken at:
40°41'58.86"N
3°45'40.14"W
If you drive past the base on the M-625 you take the first dirt road to the right. After 100 meters you can park your car near a fence (it will not be visible from the airfield). You then enter an area where a lot of cows should be walking around (not seen any, but you will see their droppings.....) and where locals collect mushrooms
If you just walk along the path, you will end of at the end of the runway. You can "hide" behind some bushes, so you will not be visible from the base.
We were there as mentioned around half an hour, close to an hour. We did not get any visit / check from the police. So not sure what will happen when you stay longer.
In the short time we were there, we saw 2 EC-135 take off, return and take off again. 1 UH-1 taking off and returning again and the CH-47 taking off and doing his thing. Besides that, there was a Cougar that did an engine run.
Good luck!
Br Erik