world's largest boulder?

[mtnkub]

According to wikipedia, Giant Rock in the Mojave desert is "the largest freestanding boulder in North America and is purported to be the largest free standing boulder in the world." (pics at https://en.wikipedia.org/wiki/Giant_Rock )

We believe we might have encountered one that is larger in Peru, in the "Archeological Cultural Landscape Rock Painting of Corani and Macusani" nature reserve, just south of the town of Aymana (which is a little west of Corani). I first noticed this boulder in 2025 on trip with Andrew Thorburn, Daniel Choquet, Vito Ricciardi and myself (Ulli Bayer) that was led by John Biggar. The attached pictures are from a 2026 trip with Jackie and Andrew Thorburn, again led by John Biggar. And the bosque de piedras in the park has plenty more interesting rock formation (as the name suggests).

Let me know if you know of any larger freestanding boulders anywhere!

[Monster5]

From a geo perspective, this is an interesting claim. I would view the JTree claim as a dubious tourist draw at best.

Mass wasting events and natural processes can produce significantly larger boulders. By reasoning, Giant Rock itself and the rock you saw were much larger millenia ago before transportation from the source (as glacial float erratics or by gravity), and erosion. As an aside, geology/ geomorphology has a fundamental rule of uniformitarianism, which is a fancy way of saying the same processes observed now also occurred in the past and vice versa. Similar to the more familiar "geologic time includes now." This is to say, nature is producing massive boulders on the daily.

[cottonmountaineering]

feels like ive seen some gianter boulders in places where there used to be glaciers, but not gonna dig through my pictures to confirm

[Wentzl]

just because I want to agree with Cottonmouth about something:

https://en.wikipedia.org/wiki/Madison_Boulder

[mtnkub]

From a geo perspective, this is an interesting claim. I would view the JTree claim as a dubious tourist draw at best.
...

feels like ive seen some gianter boulders in places where there used to be glaciers, but not gonna dig through my pictures to confirm

Yeah, when i first saw this thing i thought "Dang, that's a big rock!" and not "Dang, that's gotta be the biggest rock on earth".
So, I share the sentiment. But i'm still waiting for examples of bigger rocks coming in.

just because I want to agree with Cottonmouth about something:
https://en.wikipedia.org/wiki/Madison_Boulder

Cuz based on comparing the descriptions on Wikipedia, the Madison Boulder isn't even as big as the Mojave desert Giant Rock!

Attached John's visual size comparison of the purportedly biggest "Giant Rock" to "our" rock in Peru.

[MtnHub]

Those are certainly big.

But I recall a trip I made in the Holy Cross Wilderness/White River Natl Forest about 10 years ago when I climbed Fools Peak with a friend. On the way out there was a boulder adjacent the trail that I described in the text of my Trip Report:

“We also pass several humongous boulders, one being the largest I've ever witnessed. It is one separate rock but it is nearly the size of a 4-story apartment building. Amazing!”

Again, that was 10 years ago and I may have been tired and bug-eyed by then, but I remember it as being larger than the ones shown above.

FWIW.

[josephnephi]

Those are certainly big.

But I recall a trip I made in the Holy Cross Wilderness/White River Natl Forest about 10 years ago when I climbed Fools Peak with a friend. On the way out there was a boulder adjacent the trail that I described in the text of my Trip Report:

“We also pass several humongous boulders, one being the largest I've ever witnessed. It is one separate rock but it is nearly the size of a 4-story apartment building. Amazing!”

Again, that was 10 years ago and I may have been tired and bug-eyed by then, but I remember it as being larger than the ones shown above.

FWIW.

I was thinking of this one too! So big!

[jkirk]

I've seen bigger than Giant Rock on the approach up Wapiti Ridge in the Absarokas.
https://www.bing.com/maps?cp=44.323366% ... .1&style=h

Per LiDAR this is 76ft tall and 81ft wide

[Scott P]

The biggest boulder in Colorado I can think of is Haus Rock in Summit County. Maybe 50-60' high?

[Veory]

This block has been making the rounds on social media as well and looks bigger than the original claimed boulder. Located somewhere in WY

cube.jpg

[Veory]

Also I'd like to point out that the main image for the wikipedia page for "Boulder" is Balanced Rock here in Garden of the Gods

[jkirk]

Located somewhere in WY

44.7211718,-107.5500109