There's quite a pile of information on CIA rendition flights. They seem to have used EU member states air space [1][2]. The Washington Post suggests there was

There's quite a pile of information on CIA rendition flights. They seem to have used EU member states air space [1][2]. The Washington Post suggests there was at least some journalistic field work plane spotting in the US [3]. [1] http://www.theguardian.com/world/2007/jan/23/usa.eu http://www.theguardian.com/world/2007/jan/23/usa.eu [2] http://www.europarl.europa.eu/news/en/news-room/content/20120709IPR48490/html/CIA-flights-EU-states-must-investigate-secret-detention-sites-in-Europe http://www.europarl.europa.eu/news/en/news-room/content/2012... [3] http://www.washingtonpost.com/world/national-security/ten-years-later-cia-rendition-program-still-divides-nc-town/2012/01/23/gIQAwrAU2Q_story.html http://www.washingtonpost.com/world/national-security/ten-ye...