Uzbekistan.

Shah-i-Zinda means "the living king" in ancient language. It is the royal mausoleum of Timur's family and descendants. Travelers to Uzbekistan are tired of the yellow ruins, and Shah-i-Zinda's blue is the most touching. Thirteen tombs stand opposite each other, with a curved corridor in between. The tiles on the outer walls of the tombs make you feel like you are in a blue ocean. The domes in different tombs show off complex patterns like a show of skills. Ulugh Beg Observatory in Samarkand, the astronomical data of the solar year measured in the 15th century is only 25 seconds different from that measured by modern technology. The observatory was built in 1428-1429 by Ulugh Beg, the grandson of Timur, the big shot of the Timurid Empire. It is one of the most powerful observatories in the Middle Ages! It is equipped with a lot of high-end astronomical instruments, such as the giant wall quadrant, which is simply the "black technology" of the time. Moreover, there are a large number of astronomical books, attracting a large number of Muslim and Indian astronomy enthusiasts to do research.