Astroclimate of Northern Caucasus-Myths and reality

We list the principal stages of astroclimatic studies concerned with choosing the sites for astrophysical observatories in Caucasus and Crimea. We chow that the sites for three observatories in Northern Caucasus (Kislovodsk Mountain Astronomical Station of Pulkovo Main Astronomical Observatory of the Russian Academy of Sciences, Special Astrophysical Observatory of the Russian Academy of Sciences, Terskol Observatory) were chosen without obtaining representative statistical data in terms of the number of clear night hours and seeing. We report the data on the number of clear night hours and seeing for the 6-m telescope of the Special Astrophysical Observatory of the Russian Academy of Sciences based on results of long-term observations. We discuss the possible causes of the discrepancies between experimental and forecast data and conclude that currently none of the three observatories in the North Caucasus can be preferred because of the great variety of the methods employed and limited statistics in terms of astroclimatic and meteorological parameters for some sites.