In 1930s Boston, if you wanted to go where everybody knows your name, your nightlife destination was likely Cocoanut Grove. The club sat a few blocks south of the Boston Public Gardens, in the Bay Village neighborhood, where bunched together brick row houses shaded narrow cobblestone streets. The Grove had opened in 1927 as a venture between two big band leaders, but the joint had mob ties, as the liquor began to flow legally after Prohibition.

Formerly a warehouse space, the guts of the Grove had been decked with bamboo, satin, rattan and leather in a tropical theme. On any given weekend, the place was bursting with celebrities, food and music.

On Thanksgiving weekend, 1942, a busboy was reportedly replacing a light bulb in the Grove's dimly lit "Melody Lounge." He lit a match to aid his vision. Moments later, the palm fronds were on fire, as the flames quickly spread to the ceiling. 

The fire claimed 492 lives, as it became the second-deadliest single-building fire in U.S. history. Many of the deaths might have been avoided had a revolving door not served as the lone entrance for patrons.

The disaster led to sweeping reforms of fire codes and regulations. Afterward, the law required all public venues to have an outward-swinging door.

And this is where Cheers comes in. The Boston-set sitcom was known for its entrance. In seemingly every episode, George Wendt would swing open the front door and march into the bar, as the patrons would greet his character with a hearty, "NORM!" The front door was a major set piece of Cheers. It's where Woody and Norm said goodbye for the final time. It's where Diane kissed Sam before she walked off the show in "I Do, Adieu."

The front door swung inward, as you may remember. The Cheers bar was not up to code. The fire department could have shut it down at any time.

Bring up this piece of trivia the next time you're in a bar — if you want to be a real Cliff Clavin. 

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