Imagine Paris in the late 1800s and early 1900s. It was a time when artists were turning away from impressionism, away from naturalistic depictions of colour and light. Instead, they're more interested in symbolism, and emotion, and in creating an entirely new aesthetic style. That style is what is called post impressionism. And now for the first time, more than 100 works from that period are on display in Istanbul. Showcase's Miranda Atty went to have a look.