The Cincinnati Bengals are heading back to the playoffs this year after winning the AFC North. It's the first playoff trip since 2015, but the six-year drought is nowhere near the longest in franchise history.
That would be the 15-year period from 1991 to 2006. And the drought started with, of course, a loss (because the Bengals have never won a Super Bowl) to the Los Angeles Raiders, 20-10, in California. (Maybe the Bengals are cursed?)
If you're wondering how long that's been, the Raiders have moved twice since that game, first back to Oakland and now to Las Vegas.