On July 10, the National Oceanic and Atmospheric Administration’s Okeanos Explorer completed a 69-day, 3-stage expedition of previously unknown and poorly understood deepwater habitats.

The first leg, exploring the southern half of the Marianas Trench Marine National Monument and the Commonwealth of the Northern Mariana Islands, wrapped up on May 11. See some of their incredible finds here: 10 Stunning Undersea Creatures From the Deepwater Exploration of the Marianas

This last leg explores the northern half of these protected marine areas. Scientists captured images and video of many of the incredible creatures that live at these extreme depths, some of them never seen before or found thriving in unexpected places.

Due to its remote location, this area remains one of the “last relatively pristine marine ecosystems on the planet,” reports NOAA.

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