The Astronomical Observatory of Belogradchik or Belogradchik Observatory is an astronomical observatory owned and operated by the Institute of Astronomy of the Bulgarian Academy of Sciences. It is located near the town of Belogradchik in northwestern Bulgaria, at the foot of the Western Balkan Mountains. The other observatory operated by the same institute is the Rozhen Observatory. History Built in 1961 by a group of astronomy enthusiasts led by high school physics teacher and later chief assistant professor in Sofia University Hristo Kostov (1932-1982), Belogradchik Observatory became the first school observatory in Bulgaria. Official opening ceremony was held on 21.06.1965, by its first director Dr. Alexander Tomov (1930-2009), and was attended by much of Bulgarian leading astronomers - Acad. Nikola Bonev (1898-1979), Prof. Malina Popova (1922-2011), Prof. Tsvetan Bonchev, Assoc. Prof. Bogomil Kovachev, and already Chief Assist. Prof. Hristo Kostov. From 1964 till 1974 it was used as an auxiliary observational base for tracking Soviet satellites amidst the Space Race era. In the late 1960s additional working studies were built, adjacent to the lecture-hall and the dome. During his serve time as a director (1964-1988) Dr. Tomov referred to the Soviet experience in developing the infrastructure of the observatory, and implemented much of the methods of the Soviet astronomy school. Notable examples of cooperation are those with Acad. B.A. Vorontsov-Velyaminov (1904-1994) (see also Morphological Catalogue of Galaxies and Catalogue of Interacting Galaxies), Prof. (1918-2008), Dr. (b.1940), among other members of Sternberg Astronomical Institute (ГАИШ) and (AН СССР). In 1976 the Bulgarian Academy of Sciences took over operation. Since then the observatory was used entirely for scientific research, in cooperation with astronomers from the Department of Astronomy at Faculty of Physics of Sofia University and members of foreign institutes. By the time the Institute of Astronomy became a separate structure of the Academy in 1995, the observatory saw a notable revival. During the 1990s and 2000s Assoc. Prof. Dr. Alexander Antov, a second long term director of the observatory, modernized both its residential and scientific facilities, including the addition of a smaller dome in 1994. Its current director is Assoc. Prof. Dr. Anton Strigachev. In July 2015 the observatory marked its 50 years of operation by hosting the X annual conference of the Bulgarian Astronomical Society (SAB). Equipment The observatory started out with a single 15 cm Cassegrain telescope by Zeiss. Then in August 1969 it was replaced by a 60