The dust-covered Mars Curiosity rover has arrived at a location of fantastic intrigue.

NASA's six-wheeled robot rumbled to Gediz Vallis Ridge on Mount Sharp, a mountain the rover has slowly climbed since 2014. The ridge is evidence from some 3 billion years ago, when Mars was a wet world, replete with lakes and roaring rivers. Back then, colossal debris flows hurled mud and car-sized boulders down the mountain; eons of the whistling Martian wind then chiseled away at this material, leaving the ridge you can see below.

"I can’t imagine what it would have been like to witness these events," geologist William Dietrich, a member of the Curiosity mission team, said in a statement. "Huge rocks were ripped out of the mountain high above, rushed downhill, and spread out into a fan below."

SEE ALSO: Mars spacecraft looks back and snaps poignant view of Earth

Getting to the ridge wasn't easy. It took years to find a route there. And the journey required "one of the most difficult climbs the mission has ever faced," NASA explained. It was like running up a sand dune covered in boulders, a Curiosity engineer said.

Once there, Curiosity captured 136 images that the space agency stitched together to create the mosaic below.

In the foreground, the boulder-strewn Gediz Vallis Ridge on Mount Sharp. Credit: NASA / JPL-Caltech / MSSS

Want more science and tech news delivered straight to your inbox? Sign up for Mashable's Light Speed newsletter today.

The treacherous endeavor to the ridge also allows planetary scientists to see and study rocks from atop the lofty three-mile-tall mountain, better unveiling Mars' past. "It’s a thrill to be able to reach out and touch rocks that were transported from places high up on Mount Sharp that we’ll never be able to visit with Curiosity," Ashwin Vasavada, Curiosity’s project scientist, said in a statement.

Elsewhere on Mars, the space agency's other car-sized exploration robot, the Perseverance Rover, is scouring the dried-up river delta in Mars' Jezero Crater for potential signs of past microbial life — should any ever have existed. And astrobiologists are deeply intrigued by what could have once lived below the dried-out, irradiated Martian surface.