Built in Samarkand by astronomer-ruler Ulugh Beg, the observatory housed a giant trench sextant roughly 40 meters in radius, one of the largest and most precise astronomical instruments of the pre-telescope era.
Record no. MRB-2026-007124
Ulugh Beg's Giant Astronomical Sextant
Reference Record – Not Certified
This record is compiled from publicly available sources for reference. It has not been examined or certified by The Book of World Records.