Istanbul, Turkey

Built by Justinian in 532, this cistern provided water to the imperial palace of Constantinople.

The "New Mosque" is not so new - it was built in the 1600s. Designed by Da'ud Aga, a pupil of Sinan, Yeni Camii has become a defining feature of Istanbul's skyline.

Commissioned by Sultan Suleiman the Magnificent and constructed by the great Ottoman architect Sinan, this beautiful mosque patterned after the Hagia Sophia was finished in 1557.

This 11th-century church (later a mosque and now a museum) contains one of the finest preserved galleries of Byzantine mosaics anywhere.

This ancient Egyptian obelisk was erected in the Hippodrome of Constantinople by Emperor Theodosius I around 390, with a carved pedestal depicting the emperor and his court.

Located near Istanbul University, this is one of the oldest mosques in the city. It was completed in 1506 using materials from the Byzantine forum of Theodosius, over which it was constructed.

The Basilica of Holy Peace dates from the 6th century and was transformed into the arsenal of the Topkapi Palace in the 1460s. Today, its excellent acoustics make it a popular venue for concerts.