---

Ready for a geological whodunit?

Or more accurately, a wha’happened.

Geologist Shawn Willsey takes the classic geology field trip approach by encouraging you to figure out the story behind this apparently nonvolcanic but gorgeous spot in Yellowstone National Park.

First, a clue:

---

---

And now the field trip:

---

---

And here is more information, or if you wish, some “cheat sheets”:

• Some tips on hiking there
• A US Geological Survey article
• A lovely 1930s postcard
• A Reddit thread

---

For lagniappe:

Real hoodoos are sedimentary features. Beautiful, beautiful features…

---

---

Featured image: Michael Poland/US Geological Survey, public domain.

---