The Katzenjammer Kids
As of June 17, 2019, "Barney Google" has run for an entire century, making it the third-longest running and uninterrupted comics series of all time, after Rudolph Dirks' "The Katzenjammer Kids" and Frank O. King's "Gasoline Alley". After "Gasoline Alley", it is the second-longest running newspaper comic still in syndication and producing new episodes as of 2021.