Not really a Byzantine church - it was a Catholic church from 1325.

Possibly the oldest church left in Istanbul

This is now a medrese. My 2-year-old daughter walked into this haven of devout masculine study and made everyone giggle.

This place will doubtless be more peaceful without the Banliyo trains running behind it.

Apparently, the name of 'Gül Camii' (Mosque of the Roses) came about because when the Ottoman conquerors entered the mosque in 1453, it was full of roses left over from the prayer service that the Emperor Constantine XI had with the Patriarch before he left for defeat on the land walls.