Idaho is home to all kinds of history and mystery. While researching this history and in particular, cave homes (all in a day's work), I came across a collection of hills in Arco, Idaho that can only be described as "mysterious."

The area in question is called "Arco Number Hill" and features various numbers painted along the side of them in no particular order. I was curious as to what the reviews would be for a place that looks like something out of an 'Ancient Aliens' episode and wasn't disappointed with some of the reviews I initially read.

Google user Erik X Void wrote that his experience felt particularly unusual:

This place gave us the strangest vibes- was passing through the area with some friends and we were shocked to see the hillside covered in numbers. Interesting to say the least, but we didn't stick around for very long. Some mysteries are better left unsolved.

I wish I could share with you all of the conclusions my mind wandered to. Is it a cult? Is it aliens? Is this some ancient message telling us exactly when we'll meet our maker in the form of what the kids call a "Doomsay"?

John M. via TripAdvisor
John M. via TripAdvisor
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By this point, I'm on the edge of my seat. I have to be diving into some sort of "weird", right? Especially after I saw this review:

It’s mysterious for an ordinary person like me to see this mountain with holes and numbers. I haven’t ask anyone local yet of the history of this number holes. This mountain by the first city powered by Nuclear energy, there seems a lot of mystery here than what one can see thru the eyes.

Okay so is this literally that movie 'The Hills Have Eyes'? Would a journey into the hills to find out play out like a "found footage" horror film? Well, if you were hoping to plan your next trip looking to meet some aliens, you'll have to hold off.

John M. via TripAdvisor
John M. via TripAdvisor
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According to a sign at a nearby park, the numbers originate from an old tradition dating back to 1920. If the sign is difficult to read, here's what it says:

The number hill tradition started years ago. The graduating class of 1920 from Butte Co. High School painted the number "20" on the cliffs to symbolize their school spirit and everlasting memories. Since then the tradition has held strong and each succeeding class paints their number upon the cliffs in school colors.

It's not the work of aliens, not the work of nuclear mutants living in the hills, nope... those large numbers were the work of high school students whom I have to assume gave birth to the "Senior Prank" on that day in 1920. It sounds warm and fuzzy that they did it for their school spirit and "everlasting memories", but if this happened today? In 2022? We would be singing a whole different tune.

Do you think the numbers on the side of the hills in Arco are an eyesore or is it a cool homage to graduating classes?

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