What is a significant mosque in Istanbul, made of two former Eastern Orthodox churches and a chapel,  Istanbul High School, or Zeyrek Mosque?
Istanbul High School: İstanbul High School, (Turkish: İstanbul Lisesi , German: Istanbuler Gymnasium ) also commonly known as İstanbul Erkek Lisesi, abbreviated İEL, is one of the oldest and internationally renowned high schools of Turkey. Zeyrek Mosque: Zeyrek Mosque (full name in Turkish: "Molla Zeyrek Camii" ) or Monastery of the Pantocrator (in Turkish: "Pantokrator Manastırı" ), is a significant mosque in Istanbul, made of two former Eastern Orthodox churches and a chapel.
Zeyrek Mosque