In Search of Constantinople

'The conspirators were dressed as priests. Daggers under their arms, they blended into the crowd of clergymen who gathered in front of the Ivory Gate after dark. During the third watch of the night, they made their way into the Great Palace with the rest. Papias, the official in charge of searching visitors, was himself in the plot, so it all went according to plan... On that day, December 26, 820, the murderers entered the palace's Church of the Virgin of Pharos where an early service was about to begin... The sovereign was present at the liturgy and sang standing next to the choir - and his murderers. They jumped on him when he began singing 'By longing for the Almighty did they spurn.'... The emperor rushed to the altar and grabbed a chain attached to a censer to defend himself. He was a brave warrior, but the murderers were, as it turned out, more skilful. So, then, where exactly did the Ivory Gate stand? Where was the Church of Pharos? We cannot answer either question with any