The first experimental radio license was issued in Philadelphia in August 1912 to St. Joseph's College. The first commercial broadcasting radio stations appeared in 1922: first WIP, then owned by Gimbel's department store, on March 17, followed the same year by WFIL, WOO, WCAU and WDAS. The highest-rated stations in Philadelphia include soft rock WBEB, KYW Newsradio, and urban adult contemporary WDAS-FM. Philadelphia is served by three major non-commercial public radio stations, WHYY-FM (NPR), WRTI (jazz, classical), and WXPN-FM (adult alternative music), as well as several smaller stations.
Try to answer this question if possible (otherwise reply "unanswerable"): When did the first radio stations appear?
1922