The All-Russia Exhibition Centre site was open in August 1939. It presented various achievements of Soviet national economy. By 1989 the exhibition had 82 pavilions with the exhibition area of 700,000 square metres. Each pavilion had been dedicated to a particular industry or a field: the Engineering Pavilion, the Space Pavilion, the Atomic Energy Pavilion, the People´s Education Pavilion, the Radioelectronics Pavilion, the Soviet Culture Pavilion etc. During the Soviet times, each year the center hosted more than 300 national and international exhibitions and many conferences, seminars and meetings of scientists and industry professionals. These events attracted about 11 million visitors annually. Presently, it occupies 2,375,000 square metres of which 266,000 square metres are used for indoor exhibits.

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Adapted from Wikipedia - All-Russia Exhibition Centre