The Humboldt Hotel is a hotel located in Cleveland, Ohio.
In 2014, the deposed King of Hell Crowley held a conference with his trusted advisors about his war with the Knight of Hell Abaddon in the penthouse suite of the Humboldt Hotel. However, the demons betrayed Crowley to Abaddon who kidnapped Crowley's son Gavin to force Crowley to cooperate. After bonding with Gavin, Crowley eventually agreed to help take down the Winchesters and informed them where to find the First Blade. After the First Blade was retrieved, Crowley gave his location as the penthouse suite of the Humboldt Hotel, but discreetly warned Dean of the trap.
Upon arriving at the Humboldt, Dean sent Sam on a wild-goose chase to the basement while he headed to the penthouse to confront Abaddon. After killing Abaddon's guard, Dean battled Abaddon, augmented by the power of the Mark of Cain. Finally, Dean killed Abaddon with the First Blade. Afterwards, the Winchesters spared Crowley's life and he departed the hotel with Gavin to prevent the Winchesters from returning Gavin to his own time to die.
- The hotel can briefly be seen in Dean's flashbacks to killing Abaddon.