The most significant construction in Samarkand is the medieval observatory - “Ulugbek’s Observatory”, which had big sizes and mingled grand marble sextant for measuring the coordinates of the sun, moon and planets.
Ulugbek was a great patron of science, education and particularly astronomy. He, along with other leading astronomers from the area, built the unique and ingenious observatory just outside Samarkand, at the foot of Chupan-Ota hill range in 1428-1429. From his observatory, Ulugbek was able to map the stars and planets accurately, information that has scientific significance even today.
Explorers consider Observatory the most outstanding architectural construction of the 15th century. It is the bright confirmation of considerable science, culture and handicrafts development in Central Asia during the 14th-15th centuries. The building of observatory had to be stable to permanent earthquakes in Samarkand.
According to the archeological remnants Ulugbek’s observatory was one of the largest in the East. Ulugbek was the founder of both observatory and astronomic school in Samarkand. All scientific works of Ulugbek were based on observatory investigations. Much of the observatory has decayed through the ages. Archeological excavations have uncovered the remnants of its foundations and some instruments. In the observatory, there were the best and perfect instruments for that time. The main stationary instrument here was the huge quadrant. It was located inside the cylindrical building by 48 meters in diameter. The upper part of its meridian of 40,2 meters rose up to the flat roof of the building, its lower part (11 meters) in the rock trench has been preserved by nowadays. The spinning quadrant and the azimuth sphere were located on the roof of the building. There were also sundials inside.
After the murder of Ulugbek in 1449 his observatory was ruined down. The real location of observatory had been unknown for a long time, when finally in 1908 V.L. Vyatkin - the famous archeologist, found its remnants, owing to the document of the 17th century, where several directions, pointed to its location, were mentioned.
During the observatory excavations of 1908-1909, the remnants of one brick round wall were discovered. In 1914 explorers excavated the area of about 50 meters in diameter.
The round wall was the remains of the external wall of the cylindrical three-storied building of the observatory. The building had a flat roof and a range of certain astronomical instruments beneath. The plan of the building was rather complex. It included huge halls, corridors, passages and etc. In the center of observatory the basic instrument - sextant was located.