For hundreds of years, people looked up at sunset to the hazy peaks of California’s Santa Lucia Mountains and saw tall, veiled figures staring back. Then, within moments, the spooky silhouettes disappear.
These twilight apparitions are known as the Dark Watchers – shady, sometimes 10 feet tall (3 meters) men clad in sinister hats and capes. They mainly appear in the afternoon, and according to a recent article on SFGate.com, visitors to California have watched them perch ominously on the mountain peaks for over 300 years.
“When the Spaniards arrived in the 18th century, they started calling the apparitions los Vigilantes Oscuros (literally” the dark guards “),” SFGate editor Katie Dowd wrote in the article. “And when Anglo-American settlers began to deploy claims in the region, they too felt the sense of being watched from the hills.”
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A famous observer who sensed the presence of the Watchers was the American author John Steinbeck. In his 1938 short story ‘Flight’, a character sees a black figure lurking at him from a nearby hilltop, ‘but he quickly looked away, for it was one of the dark onlookers,’ Steinbeck wrote. “Nobody knew who the guards were or where they lived, but it was better to ignore them and never show any interest in them.” (This was a family obsession; Steinbeck’s son, Thomas, went on to co-write a book on the Watchers with painter Benjamin Brode, Dowd wrote.)
So, who – or what – are the Dark Watchers?
According to Dowd, one theory is that they are merely fabrications of the observer’s pattern-seeking mind. In other words, it’s a classic case of this pareidolia: a psychological phenomenon in which an observer’s brain finds patterns or meaning in a vague or random image.
The phenomenon is why some people see it Muppet faces on the moon, or the face of Jesus on burnt toastIn this case, common shadows on Santa Lucia’s hilltops can be interpreted by the viewer’s brain as tall, cloaked figures (the Watchers usually appear in the late afternoon, when long shadows adorn the hills).
This pattern-seeking effect could be enhanced by the presence of fog or low-flying clouds, according to Dowd. Shadows against clouds are responsible for another infamous illusion known as the Brocken ghost.
“German residents near the Harz Mountains have for centuries reported seeing shadowy figures on the Brocken Summit,” Dowd wrote. “In reality, the Brocken ghost happens … when shadows – like those of a hiker – are cast on particularly misty mountain peaks. When the sun is behind the observer, the mist plays with the shadow, making it look massive and menacing. “
The spectral figures are usually surrounded by a rainbow-colored halo, produced by sunlight broken down by water droplets in the mist or clouds, according to the BBCWhile it is common in the Harz Mountains where fog often creeps in at low elevations, you can see the effect on any misty mountain slope with the sun behind you and the clouds below. You may have seen it yourself from an airplane window; Cruising between the sun and the clouds, the plane can cast a rainbow-rimmed shadow on the clouds below that appears supernaturally large.
So it’s possible that hikers in the Santa Lucia Mountains will only stare into their own shadows when the Watchers come to watch. (Sorry, Steinbeck.)
Originally published on Live Science.