In 1980, Haring happened upon a highly effective medium which allowed him to communicate with the wider audience he desired, when he noticed the unused or expired advertising panels covered with matte black paper in a subway station. He began to create drawings in white chalk upon these blank paper panels throughout the subway system. Between 1980 and 1985, Haring created these "subway drawings" at various stations. The images became familiar to the New York commuters, who would often stop to engage the artist when they encountered him fast at work (since it was an "illegal" act for which he would later get arrested numerous times.) The subway became, as Haring said, a "laboratory" for working out his ideas which he would later re-visit in other mediums such as paintings and prints.