The Hippodrome was at the center of Greek and Roman civic life. Here citizens of all classes would gather to watch chariot races. Istanbul's dates back to the start of the third century AD, when it was still called Byzantium. When Constantine moved the capital here, one of his first acts was to expand the Hippodrome. For the next millennium it was a crucial part of the city, but fell into disrepair after the Fourth Crusade.
Though the area is still known as the Hippodrome, don't let the name fool you. Aside from the layout of the small park that sits on the site today, there is little evidence of the former racetrack. The grandstands, which could seat 100,000 people, have been demolished, but there are several interesting remains. The Egyptian Obelisk of Tutmosis III dates to the 13th century BC. This solid block of granite was brought here by Emperor Theodosius I from the front of the Karnak Temple in Egypt. The Serpentine Column was taken from the Temple of Apollo at Delphi in the 4th century by the Emperor Constantine. This bronze column depicts three intertwined snakes supporting a golden bowl.
The Magnetic Column was installed by Constantine VII in the 10th century to support a pulley system to shield spectators from the sun. The Fountain of Wilhelm II was built by the Germans to commemorate the kaiser's visit in 1895. The hippodrome's most spectacular monument was the massive statue of four bronze statues currently residing in Venice's Basilica of St. Marco.
This small park is right across the street from the Blue Mosque. It's definitely worth a quick look for the interesting monuments, and is a good place to relax during a busy day of sightseeing.
Location: Meydani (Horse Plaza), Sultanahmet