Where 100,000 Byzantines once roared at chariot races, you'll now find a quiet park dotted with ancient monuments. The Egyptian Obelisk — carved 3,500 years ago at Karnak and shipped here by Theodosius — still stands impossibly straight. Nearby, the Serpentine Column from Delphi has been here since 324 AD, making it one of the oldest surviving antiquities in the city.