Walking along Divan Yolu from Sultanahmet to Beyazıt Square and the Grand Bazaar, you come to Çemberlitaş (stone with hoops), a tall, obviously very old and dismal-looking porphyry column (map).
It was erected on May 11, 330 by Constantine the Great to celebrate the designation of Constantinople as the new capital of the Roman Empire.
The column was the centerpiece in the Forum of Constantine, a grand colonnaded plaza which may have resembled the one designed by Bernini and built in front of St Peters basilica in Rome. Statues of pagan gods and Christian saints decorated the forum.
Hoppa offers low cost transfers at Çemberlitaş and the surrounding areas.