The excavation of 37 different monuments has been undertaken by the National Institute of Archeology and Ethnology of the National Academy of Sciences of the Republic of Armenia and the results are satisfying. As the director of the Institute Pavel Avetisyan mentioned in the conversation with "Armenpress" not only excavations, but testing and research have been executed in those ancient places. Excavations in 10 archeological units are still being carried out. He said: "This year we have carried out excavation in Masis hill nearby Yerevan, which is a monument dating back to the Stone Age and probably the most part of the hill was devastated during 1970s, but the layers are still safe. The Armenian-American expedition has already discovered the constructions with round plan and dug out a large amount of instruments from bones and stones."