San Francisco has no shortage of harrowing historical episodes — earthquakes, fires, plagues — but one of the city's most horrifying and least-remembered tragedies happened on Thanksgiving Day, 1900, and it started with something painfully relatable: people trying to watch a football game for free.

The annual Berkeley vs. Stanford game was the sporting event of the season, and a crowd of fans who either couldn't afford tickets or simply didn't feel like paying found what seemed like the perfect solution — the roof of a glass factory adjacent to the field. Free sightlines, no admission fee. What could go wrong?

Everything, as it turned out. The roof buckled under the weight of dozens of spectators and collapsed, plunging men and women into the factory's industrial interior — directly into a kiln containing an estimated 14 tons of molten glass. Take a moment to process that. A holiday afternoon of college football ended with people falling into a vat of liquid glass heated to thousands of degrees.

The carnage was as nightmarish as you'd imagine. And yet, in a detail that might be the most darkly revealing footnote in San Francisco sports history, the game continued. Stanford won. As one local put it: "Apparently, people dying en masse in a glass factory next door wasn't enough to stop the game."

It's a grim slice of city history that almost nobody knows about. And honestly, it reads like a parable about the things San Francisco has always struggled with — inadequate infrastructure, spectacles that overshadow human cost, and the uncomfortable question of who bears responsibility when disaster strikes on someone else's property.

There's no modern policy lesson to extract here, just a reminder that this city's history is wilder, darker, and more layered than most residents realize. Over a century later, the factory is long gone. The rivalry lives on. And somewhere in the historical record, the names of those Thanksgiving fans — the ones who just wanted to watch a game — are mostly forgotten.

Some free seats cost more than you'd ever want to pay.