It floats upright in Oregon's Crater Lake , but it's not a buoy or a pillar. It can be seen in different locations in different days, depending on the weather. In fact, it's not connected to anything to tether it to the lake's floor. Known as the "Old Man of the Lake," this mysterious phenomenon has perplexed park staff and visitors for decades.

The Old Man is actually a hemlock tree stump that somehow remains upright in the water, even as it moves. Indeed, the Old Man goes along with the whims of the wind and waves.

The 30-foot-long stump was first observed and documented over 100 years ago by geologist Joseph S. Diller, according to the Crater Lake Institute , bobbing a bright white about 4 feet above the water. Years later, when Diller observed the Old Man once again, it was in a new place within the lake.

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At first, people figured the Old Man was just a weathered, aged tree measuring the lake's depth over time, a theory quickly debunked when Diller and others realized the tree was moving.

Park naturalist John Doerr even plotted the path of the Old Man in 1938, reporting that the tree traveled more than 60 miles during his three-month-long observation.

So why hasn't the Old Man sunk?

The most common theory, posited by Doerr, is that the tree was initially held down by heavy rocks after a landslide and soon became waterlogged. The exposed part of the stump has dried and aired out in such a way that keeps the tree perfectly balanced and afloat in an eerie equilibrium.

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Over the decades, the Old Man has become a celebrity - and a legend. Local lore has it that this well-known character can even control the weather. According to Atlas Obscura , the myth goes back to a submarine expedition in 1988, when the crew tied up the Old Man, bringing a storm ... until they untied him.

The Old Man may not bring about changes in the weather, but he certainly enables onlookers to gain a better understanding of it. Doerr's own observation of the tree gave him a better understanding of how the wind affected the lake's currents. Of the tree's path throughout the months he observed it, Doerr wrote: "This certainly indicates that during that time there was a prevailing southerly wind which was deflected locally by the crater walls to the extend that numerous eddys and cross currents were created, thus accounting for the continuous back and forth movement of the floating stump."

Whether or not the Old Man of the Lake is truly a supernatural force, today he floats his own path to wherever the wind will take him.

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