Most People Don’t Realize An Underground River Flows Right Through Wyoming

Sinks Canyon State Park in Wyoming features the Middle Fork Popo Agie River, which mysteriously disappears into an underground limestone cavern.

Now you see it, now you don't! There's a beautiful river that makes its presence known as it flows through the great state of Wyoming. That is until it performs a vanishing act of sorts. One minute it's there, and the next minute, the earth has completely swallowed it up. Most people don't realize this river in Wyoming flows underground...or does it?

This road isn't the only thing that meanders through this state park in Wyoming.

Located in the Wind River Mountains, six miles southwest of Lander along Wyoming Highway 131, is Sinks Canyon State Park. Sinks Canyon State Park is named for the Middle Fork Popo Agie River. This very special river is the heart and soul of the park.

This unusual body of water is 54 miles long, and flows around any obstacle that dares try to stand in its way. The water flows just like any other river until:

...it flows into an underground limestone cavern, where it completely disappears.

This is where the limestone begins to work its magic on the unsuspecting waters of the river.

The limestone formation was formed by glacial movement during the Ice Age. This, in turn, created extensive underground fissures and high canyon walls throughout the park.

The rushing river flows into this underground limestone cavern through cracks and fissures in the rock. This section of the river is known as "The Sinks".

The amount of water flowing into "The Sinks" varies throughout the year. The water flow depends on the time of year and the amount and form of precipitation.

The water level drops in the winter and swells dramatically in late May and early June during spring runoff from the melting snow. What should only take minutes transforms into hours; it takes over two hours for the water to travel underground for 1/4 mile on its unusual journey.

It is believed that there are many winding underground passages that the water has to work its way through.

The Popo Agie River eventually emerges by trickling out of the hillside into a protected trout pool called 'The Rise' before it continues on its path down the canyon.

This is an amazing feat for such an ordinary Wyoming river!

For another unusual Wyoming river, check out The Most Unique River In The World Is Right Here In Wyoming. What do you think? What are your favorite rivers in beautiful Wyoming?

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