Salt marshes like this one make up a very important habitat for wildlife, especially migratory birds, which makes the Great Salt Plains a great stop for nature lovers.
But what makes this a really unique experience is that you can go crystal digging. If you dig a small home in a designated area, you'll soon find clusters of selenite crystals than naturally form in the salt flats, and you're allowed to remove them and take them home as a really special souvenir!
How did a salt flat form in Oklahoma? I'm glad you asked. You see, millions of years ago, the central part of North America was covered by a shallow ocean. As the North American continental place rose, the oceans receded, leaving behind the dry land that would become the great plains. However, little pockets of salt water got trapped as the surrounding land rose too high, forming lakes made of salt water, including one in northern Oklahoma. Over time, the water in this lake started to evaporate, leaving behind more and more concentrated salt water. Eventually as the water level in the lake continued to fall, it became saturated, and the salt began crystallizing out. What was left behind on the former lakebed was a vast plain covered in salt.
The entrance to the crystal digging area is in the southwestern part of the salt plains. After a brief stop at the observation platform to get an overlook of the area, I continued on to the digging area.
I shortly arrived at the digging area, which was clearly marked. You can see the dark patches of upturned earth where other people had been digging in previous weeks and months. They actually have several designated digging fields, but only one is open in a given year - that gives the crystals time to regrow in previously used areas.
Once I found the crystals, I was actually glad to be digging with a paper cup instead of a metal shovel. The crystals are actually somewhat fragile. I broke pieces off of a few of them with the cup as I was trying to dislodge them from the ground. A shovel would have gone right through them and shattered them all to bits. Thank you hotel cup!
After only a short time, I had several crystals and decided I was satisfied enough to stop. If I had kept going I'm sure I could have found many more. I've seen other people's photos that have even found large masses of crystals all stuck together. The crystals are a mineral called selenite - a form of gypsum. Selenite is usually transparant and glassy, but the selenite here (due to the soil composition) contains these brown hourglass-shaped inclusions.
My favorite was the short Sandpiper Trail that takes you through the wetlands on the northern edge of the refuge. The salty water provides a great habitat for migratory shorebirds and other animals. You may see different species depending on what time of year you visit. I was here in April.