There’s a 1,000 year old forest hidden under the surface of Lake Washington

If you’re afraid of what lurks below Lake Washington when you swim, you probably don’t want to keep reading. But because it’s swimming season we thought we should clue you in on one of the lake’s best secrets. The lake in its 214-foot depth has some pretty unexpected things hidden at the bottom including planes, cars, and even an entire forest.

Sounds improbable right? Before we get into details know there’s not just one but actually a few in Lake Washington and one in Lake Sammamish.

Here’s the short story of how the forests came to be underwater according to Oregon State University. Over a thousand years ago, a massive earthquake shook the region, sending chunks of Earth plunging into Lake Washington and Lake Sammamish according to the Department of Natural Resources (DNR). Both slides had enough dirt to keep the trees submerged until today.

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Lake Washington Underwater Forest from Dan Warter (DCS Films) on Vimeo.

Due to how dark the bottom of Lake Washington is, it’s unlikely you’ll be able to see them for yourself unless you plan on doing some deep diving with proper lighting equipment. That means you don’t have to worry about running into these sleeping giants but you can check them out in the video above if you’re curious.

Keep in mind that these days most of the trees are bare due to their age and how busy the lake is. They’ve remained standing due to low oxygen levels in the water and have become extremely hard due to the tree sap turning into minerals.

The trees in Lake Washington are located northwest of Kirkland and another two forests are located off the southeast and southwest shores of Mercer Island. In Lake Sammamish, you can actually catch a glimpse of the underwater tree tips by kayaking at Greenwood Point.

Information on the Lake Washington and Lake Sammamish submerged forests is from Oregon State University and the DNR. All information is accurate as of publication date.