Photo: Petar Milošević · CC BY-SA 4.0 · Wikimedia Commons

Ulugh Beg Observatory

On Kuhak hill in Samarkand lie the remains of one of the most advanced astronomical observatories of the 15th century. Standing by the huge underground arc once used to measure the sky, you can see how seriously the Timurid court took science.

History

The observatory was built in the 1420s by Ulugh Beg, grandson of Amir Timur and ruler of Samarkand. Sources differ slightly on the exact start and completion dates, but it was generally ready around 1428-1429. Ulugh Beg had a deep interest in mathematics and astronomy and brought leading scholars of the age to his city.

Jamshid al-Kashi was the first director, followed by Qadi Zada al-Rumi and then Ali Qushji. The observations made here fed into the Zij-i Sultani, completed in 1437, a star catalogue and set of astronomical tables that remained influential in both East and West for centuries.

After Ulugh Beg was assassinated around 1449, the observatory declined. Accounts differ on the details: some say it was destroyed soon afterwards, while others say work continued for a time under Ali Qushji. The site was eventually forgotten, until the Russian archaeologist Vassily Vyatkin uncovered its remains in 1908.

What to see

Little of the original building survives above ground. What you see are mainly the foundations and the buried part of the great instrument, a huge arc cut into the bedrock and lined with marble. Degree markings and brick stairways along its sides can still be made out.

Reconstructions suggest a three-storey cylindrical building, but there is no standing structure to walk into today. A small museum is usually found on the site, with exhibits on Ulugh Beg and the scholars who worked with him; check its current status before you go.

Visiting tips

The observatory sits on Kuhak hill, northeast of central Samarkand, and is easy to reach by taxi or local transport. Much of the visit is outdoors, so in summer early morning or late afternoon is more comfortable, and good walking shoes help.

Entry conditions, opening times and fees can change, so check before you go. It fits well into a day with other Samarkand sights such as the Registan and Shah-i-Zinda, but give yourself time to read the museum displays, as they make the ruins much easier to understand.