Evans Plunge, Hot Springs

Evans Plunge isn't your typical water park. This indoor gem in Hot Springs, South Dakota, runs on pure geothermal spring water that maintains a natural temperature year-round. The main pool is massive by historic standards, built back in 1890, and the mineral-rich water creates this unique experience you won't find anywhere else in the region.

The water stays around 87 degrees naturally, so you can swim comfortably even when it's freezing outside. The facility feels more like a community swimming pool with serious historical character than a modern water park. You'll find a large swimming area perfect for laps or just floating around, plus some smaller pools and areas for kids.

The water has this slightly different feel because of all the minerals, and locals swear by its therapeutic benefits. It's particularly great for families with younger kids since the water temperature is so comfortable and there aren't any intense slides or attractions that might overwhelm little ones. The indoor setting means you can visit any time of year, which is huge in South Dakota winters.

Don't expect flashy slides or wave pools - this place is all about the unique spring-fed experience. The building itself has character, with that classic indoor pool echo and vintage feel. I'd recommend bringing water shoes since the deck areas can get slippery, and definitely plan to spend a few hours just relaxing in the mineral water.

It's surprisingly busy with locals, especially during colder months, so weekday visits tend to be more peaceful. The entry fees are reasonable compared to big theme park water attractions. This spot works best for people looking for a unique, relaxing water experience rather than adrenaline-pumping thrills.

It's genuinely one of the few places in the country where you can swim in natural hot springs indoors year-round.