If you are looking for a sweet day trip out of the Tri-Cities, why not check out the Blue Rhino Cave near Coulee City?

The cool thing is that this cave isn't just named after a Rhino, it once was a Rhino!

It's a pretty cool travel destination and if you like the unique, you should check it out, but always remember safety first when you are exploring a cave.

Here are the details of the cave from Atlas Obscura 

The rhinoceros-shaped cave was made by highly fluid, rapid-moving basalt that was once a mature Diceratherium (an ancient ancestor of the modern rhinoceros) bull grazing on prairie when the eruption started. Its escape route was cut off by a lake, which led to the Diceratherium’s fiery fate.

Death by lava sounds like a terrible way to go, but on the bright side, the Diceratherium was probably killed by the heat and poisonous gases before it was eventually covered by the lava. The remaining fluids in its corpse cooled the molten rock, which hardened it into its present shape.

In the late 1940s a crew from Berkeley made a cast of the interior of the cave. The cast is on display at the University of Washington Burke Museum in Seattle. Some bone fragments were found. The largest is the left mandible with broken teeth, indicating a mature animal comparable to a Diceratherium ancestor.

Because of its size, a crawl through the cave is not for everyone. However, if you take a flashlight with you, you may be able to see the bellybutton.