You've just got to see this! I'm not kidding when I say it's unbelievable. There are arguments about how many true intermittent springs or periodic springs there are in the world. While there are many continuous springs, intermittent ones are very few in number. But there are at least three; one in Jerusalem, one in Italy and one in our own backyard. Wyoming. My mom grew up near there and so literally it was in her childhood backyard. It makes us happy to go back with her and visit that little town and every time we do, we hike to Intermittent Springs!
Geologists explain that it acts like a siphon; filling up and then spewing out. This happens every 18 minutes. It's crazy. And really, really worth the easy hike. If you are ever going through Afton in the late summer or fall, you must check it out.
If you do go and the water is running while you are hiking up, just stop where you are. Wait for the spring to stop running and then you can get to the top and wait there to watch it start again.
The intermittent spring is in Afton, a couple hours South of Jackson Hole, WY and another hour from Yellowstone. Here it is on google maps. If you are hungry afterwards, Hegges there in Afton is good and Tootsies up the road in Thayne makes a good pizza.
Here is a good video about it from the University of Wyoming.
