I first encountered the Orthodox monasteries of the Meteora in PLF's Roumeli, in a chapter called "Monasteries of the Air." All of them are atop high, rocky peaks, reminiscent of Bhutanese Buddhist monasteries. They are not nearly as well known as those of Athos. PLF gives a traveller's perspective, Nicol that of an academic.
This is an early work of Nicol, who was a student of Runciman and a distinguished Byzantinist. He approaches the Meteora and its monasteries systematically, beginning with introductory chapters on Byyzantine monasticism and the history of Thessaly in the medieval period. Nicol then covers the monasteries and their founders, partly chronologically and partly by foundation. His work is based both on primary sources (mainly early chronicles and travel writers, along with inscriptions) and a solid first-hand knowledge of the region. The descriptions of buildings, etc. sometimes become tedious. A map and some plans would have helped, although there are some fine B&W photographs of the monasteries clinging to their rocky perches. More on the actual lives and spiritual practices of the monks would have been welcome.