[Right_Wing_Madman]

Where do most Byzantine-era remnants reside today?

Nowhere. The Turks destroyed almost all of those treasures.

Thousands of busts and statues remain from the Roman Republic/Empire because the Church and Italians did such a great job protecting and preserving them. Almost no remnants remain from the Byzantine Empire.

[marktwain]

Nowhere. The Turks Muslims destroyed almost all of those treasures. Fixed it.

Muslims destroy the history of wherever they occupy. It is deliberate policy.