What is the longest-running comic strip still in print?
That would be The Katzenjammer Kids, which has been running since 1897. Created by Rudolph Dirks, it is also the first comic strip ever to tell a story using a series of panels. The strip's publisher, Hearst, handed it over to Harold H. Knerr when Dirks took a leave of absence. It later was passed along in turn to Doc Winner, Joe Musial, and the current artist, Hy Eisman.
For more information on the history of comics in America, we invite you to check out our Comics Timeline.