Constantine crowned this pillar with a gilded statue of himself as the sun god when he inaugurated his new capital in 330. Stacked from great drums of porphyry — the deep-purple Egyptian stone reserved for emperors — it rose at the centre of his round forum on the Mese, the processional spine of the city, and relics of astonishing pedigree were said to be sealed beneath it. The pillar has marked this spot since the city's first day.
The centuries have not been kind, and that is much of its power. You look up at a scarred, rust-banded shaft, its porphyry cracked by earthquakes and blackened by the fires that earned it the English name Burnt Column; the iron hoops holding the drums together give the Turkish name Çemberlitaş, the hooped stone. The statue crashed down in a gale nine centuries ago, killing passers-by; a cross later stood in its place, until that too was taken down. Today the column rises from a walled Ottoman base beside the tram line on Divan Yolu, and most of the city hurries past without looking up.