I'd watched this picture in a theater, only with a few audiences. Besides, it was the only theater which was screening this movie in a 5-million-populated city. I suppose, that's enough to say how "underrated" it is.
Primarily, this movie is result of an enormous effort. Some sequences were probably waited to take for months; all scripted climatic changes were in natural schedule. Peaks, caves, cliffs... Every kind of topography had been background for strongly rough shots. Furthermore, acting of all inexperienced locals are astonishing. I would argue that real actors wouldn't act as good (natural) as locals did.
"Human against nature" is a strong theme if it's adapted into screen properly. A contemporary movie "The Revenant" is a powerful one, especially in cinematography, however it's naturalism imitates the reality. On the other hand, Cold of Calandar avoids the exaggeration of mankind's superhuman resistance. This movie is reality's itself: pure relentless nature and it's eternal and unguarded toy: human.
Mustafa Kara is a promising director and fairly young (36) as well. Hopefully he keeps up his good work.