Pick up a hand spade and start digging for your very own geode!
Explore South Dakota's Biggest Mystery

Attractions
Hours of Operation
We can get very busy during the summer. We strongly suggest that you purchase tickets online in advance to ensure you get a spot on one of our tours.
April & October - 9:30AM-4:00PM Friday, Saturday and Sunday (tours every hour from 10:00am-4:00pm)
May & September - 9:30AM-4:00PM (tours vary daily from 10AM-4PM)
June, July & August - 9:00AM - 6:00PM (tours every ten minutes from 9:30AM-6:00PM)
Holidays (Memorial day, 4th of July, Labor Day) - 9:00AM-5:00PM (tours every five minutes from 9:30AM-5:00PM)
Family Fun Attractions For All Ages
Combine a 40 minute cabin tour with our other activities for hours of family fun that will turn into a lifetime of memories. After you tour our Mystery House and dig up some treasures in our geode mine why not cool down with some ice cream? Then browse our huge gift shop full of souvenirs from the Cosmos Mystery Area and the Black Hills of South Dakota. Bring a picnic lunch and enjoy it on our deck that overlooks the amazing surrounding wilderness.

You'll wonder how it all works at this mysterious attraction where you can stand on the walls and balls roll uphill.

Hours of fun for the whole family!

Don't forget to check out our Gem Mine during your visit!
Separate and recover gems, fossils, arrowheads and minerals using our sluice. Match your findings to your gem index to discover what types of rocks you’ve collected! A hands-on activity for the whole family to enjoy! We offer several different options of mining dirt in our Gift Shop.
More InformationOur Happy Customers

Our Story
In 1952, two college boys searched the Black Hills looking for the perfect spot to build a summer cabin. Upon their search, they stumbled into the mysterious world of the Cosmos.
Our Story
I had heard about this place before, but I thought it was all hype. I was wrong. It is a really cool place, and I was amazed almost from the start. Definitely worth the price of admission. If you can figure it out, please let me know.
Makes your brain go topsy turvy trying to figure out what's happening. The kids LOVED it!
My husband has been wanting to go here for a long time and we were finally able to make that happen. Our kids were just as blown away as we were and had a great time! It is such an extraordinary place to visit and you can't even explain what is happening. If you are able to go then you definitely should. There are so many things that you can't even explain and we'll just keep you wondering not only when you're there but once you leave. Our tour guide was not only funny but just a great guy to have as our guide. The kids really enjoy doing the geo find at the end of the tour also. They even have a small little gift shop.
I've wanted to go since I was a kid and finally made it with my own children. We all loved it. So glad there was parking in the shade and cool weather as we traveled with pets.