Thor’s Well is among the oceans’ most perplexing natural wonders, appearing like a bottomless sinkhole that looks as though it’s draining the sea of its water. In actual fact, Thor’s Well is the remains of a sea cave, carved out by water, whose ceiling collapsed.
Found in the Cape Perpetua Scenic Area along the Oregon coast, Thor’s Well looks very different depending on the time of day or, more specifically, the tide. At high tide, water briefly conceals Thor’s Well before appearing to drain through – which is why the novelty formation is sometimes called “the drainpipe of the Pacific”.
During storms or choppy waters, Thor’s Well’s contents foam up and can shoot out of the top in a dramatic spray of sudsy-looking water. This is arguably the best time to photograph Thor’s Well, but it’s also the time at which anyone who gets too close is at the greatest risk of getting sucked in.
While Thor’s Well reportedly hasn’t yet claimed any lives, there are a few people who have been injured as the strong currents and powerful waves surrounding the hole have knocked them against the rock. With explosions from the well reaching up to 6 meters (20 feet) high, it’s easy to see how things can quickly take a turn.
At low tide, Thor’s well is considerably less intimidating as water passing under the bowl can be seen bubbling about quite peacefully. Here, the sinkhole’s residents become apparent: mussels, barnacles, and starfish can be seen lining the hole, which is about 3 meters (10 feet) in diameter.
As for Thor’s Well’s rather dramatic nickname, it’s in honor of the figure in Norse Mythology. Thor, with his big old hammer, is said to have smashed the hole into Oregon’s coastline – an explanation that’s undeniably sexier than a crumbling sea cave.
Made from the same basalt that lines the Oregon shoreline, Thor’s Well is estimated to be 6 meters (20 feet) deep and is at its explosive best around an hour before high tide as it begins to fill with fizzing seawater. Visitors wanting to gaze into the mythic bowl will find it south of the Cape Perpetua Visitor Center in Cook’s Chasm.
Millions of years of the powerful Pacific have transformed this stretch of Oregon’s coastline into something of a theme park for dramatic ocean activities.
Elsewhere in Cook’s Chasm, you’ll find spouting horns – a playful coastal character that is effectively an ocean geyser powered by seawater rushing in through a narrow hole. The effect is exploding fountains of water which can erupt quite unexpectedly, like the spout of a whale bursting through the ocean surface.
Sneaker waves are also of particular concern here, having killed many people in Oregon according to the National Weather Service. Also known as sleeper waves, they are particularly large waves with a high concentration of sand which can emerge suddenly and without warning.
While very dangerous, sneaker waves are rare, but it pays to be vigilant when exploring Cook’s Chasm. If in doubt, check the NWS public alerts for information on weather warnings that could increase the likelihood of sneaker waves.
An earlier version of this story was published in August 2022.