The most famous underground cistern in Istanbul is usually packed and no one knows the recently restored Theodosius Cistern that is at least 100 years older than St. Sophia Church. This cistern had been closed for ages and has now been totally renovated and restored (it took 8 years). As a culture and Byzantium lover, this cistern is the highlight of the city and not to be missed. It’s the new Byzantium in town as I call it. The Turkish name is Şerefiye Sarnıcı, just in case you need to get directions. It’s very close to the Cistern of Philoxenos. This beautifully restored cistern is made of brick lined with hydraulic mortar. Its roof consists of a series of brick vaults, supported by 32 marble columns (8 columns and 4 rows) with Corinthian capitals. This 1,600-year-old cistern is older than the Hagia Sophia and an important cistern. It is not possible to find another like it in the world. It was built in the fifth century and has been known as the Theodosius Cistern since the 19th century. We see a cistern that stands still for nearly 1,600 years. Possibly, it, which features 32 columns inside, was built in the period of Roman Emperor Theodosius II. Having been built in the period of Roman Emperor Theodosius between 428 and 443, the Theodosius Cistern will become an important spot for all visitors.