Lycée Notre Dame de Sion Istanbul (Turkish: Notre Dame de Sion Özel Fransız Lisesi) is a French private high school located in the Harbiye, Şişli neighbourhood of Istanbul, Turkey. It was founded in 1856. The high school was established in the Ottoman Empire as a missionary school for girls only. It was later transformed into a co-educational status. The Medium of instruction from preparatory class through twelfth grade is in the French and Turkish language, and takes four years after a preparatory class of one school year. Source: Wikipedia (en)