Location of the terrorist hideout
To whoever it was in the FAQs that wanted to know the location of the hideout where the rebels held the kidnap victims: yes, it is in Greece. It's the Roussanou monastery, one of the six remaining Meteora monasteries in the Tessaly district. It's an active nunnery and also a pretty popular tourist spot, despite the fact that you have to make a pretty steep climb to get to it. The monasteries were apparently built on the tops of rock pillars like that so that they would be difficult for the Turkish invaders to attack. That painting by which McCabe identifies the location is actually in the Roussanou monastery, so that much at least is accurate.
The lads who did the flying in the movie, the Wills brothers and rest of their flying team, Chris Price, Dean Tanji, etc. actually did fly in the region (no special effects), which is about the last place a hang glider pilot would voluntarily fly, due to the ruggedness of the terrain, which created a ridiculous amount of turbulence in even the lightest winds. They had guts... Or maybe they were just paid lots of dough.