Until 1951, motion pictures were filmed on nitrocellulose which is highly flammable. When it burns, it produces oxygen as a byproduct, so dousing it with water won’t put the fire out. In fact, when “nitrate film” catches fire, it is very hard to extinguish; film projection rooms, in order to keep the fire from spreading, were often coated in asbestos. On top of that, nitrate film, as it degrades, is known to spontaneously combust. All together, a lot of old films — especially silent films — are lost forever.

And many more would have been lost, except for an odd little quirk which sent them almost into the Arctic Circle.

If you want to watch the silent films Gentlemen Prefer Blondes (1928), The Great Gatsby (1926), or El Apostol (1917, and the first animated feature film ever made), the sad truth is that you can’t. All three are widely agreed upon to be gone forever. The last known copy of El Apostol, for example, was in producer Federico Valle’s private collection, but — as you may have guessed — burned when Valle’s studio caught fire. This wasn’t a terribly uncommon occurrence, and because of this, many of the first significant films in motion picture history are long gone. Per one estimate, 85-90% of movies from the silent film era are gone.

But in 1896 a seemingly unrelated thing happened — someone found gold in the Yukon. The Klondike Gold Rush (better known as the Alaska Gold Rush in the United States) began as tens of thousands went north, settling at the confluence of the Klondike and Yukon Rivers. That area became known as Dawson City, Yukon, and was home to as many as 40,000 people that year. While the town’s population would quickly wane to 5,000 by the time the town incorporated in 1902, it was significant enough to warrant attention from the media and entertainment industry. Many silent films made their way to the town, but the cost and difficulty of transporting them to the icy northwest was considerable. Movies sent to Dawson City went there at the end of their tenures as actively featured films; the Dawson City library was the final intended destination of hundreds such films.

For some reason — this is speculation, but it’s probably a bad idea to have hundreds of highly flammable time bombs in a library full of (paper) books — many of the films were dumped into a condemned, empty swimming pool in 1929. An ice hockey rink was built above them, and they fell out of the memories of society, effectively lost like all the others. But in 1978, the city decided to build a new recreational complex on the same site, and a bulldozer digging a new foundation came across this treasure trove of film-making history. The permafrost had kept the movies in decent-enough condition, and roughly 500 films were saved.

Bonus fact : In 1939, an author named Ernest Vincent Wright wrote a 50,110 word novel titled Gadsby. The story is about a man, the protagonist John Gadsby, who builds up his small town of Branton Hills into a city of over 60,000 residents. The book itself, though, isn’t all that good, using some odd language and curious turns of phrase. This isn’t a knock on the author, though — the odd linguistics were intentional. Gadsby, by design, never uses the letter “e.”

From the Archives: Mickey Attempts Suicide: How a silent movie almost cost us Mickey Mouse.

Related: Gadsby.