Constantinople Observatory of Taqi ad-Din
Constantinople, Ottoman Empire · built 1575
The Constantinople observatory of Taqi ad-Din, founded in Constantinople (today Istanbul) by Taqi ad-Din Muhammad ibn Ma'ruf in 1577, was one of the largest astronomical observatories in the pre-modern world. However, it only existed for a few years and was destroyed in 1580.
Observatory data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).