Hagia Sophia: Istanbul, Turkey

Built between 523 and 527, the Hagia Sophia, first a church, then a mosque, and now a museum, is a masterpiece of Byzantine architecture.

The interior boasts intricate mosaics, polished marble floors and a dome that will leave your neck sore from constant gazing. Like the similarly astounding Pantheon in Rome, the Hagia Sophia is crowned by a massive dome, sitting upon a rectangualr building. The architectural problem this poses is solved by four triangular, concaved sections, called pendentives, which share the dome’s weight equally and visually lend an air of lightness to the building.
In this particular section of Istanbul, artistic and architectural treasures abound. While there, head towards the Byzantine Hippodrome (horse-racing track of antiquity ) where you can check out the 3500 year-old Obelisk of Theodosius, the Museum of Turkish and Islamic Art, and the Hagia Sophia inspired Blue Mosque