Something Incredible Happens at this MN Park Only Twice a Year

At one particular Minnesota state park, there's something really cool that happens only twice a year: once in the fall and once in the late winter/early spring. One of those instances is coming up next month, so we need to make plans!

We always get all four seasons here in Minnesota but they don't always line up with when the calendar says they 'should' happen.

However, on the first day of spring and the first day of fall according to the calendar, this special event takes place at Blue Mounds State Park.

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The Spring and Autumnal Equinoxes (AKA: The First Days of Spring and Fall)

The spring equinox and autumnal equinox are just fancy ways to say 'The position of the sun says it's the next season now'.

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The Almanac writes it out more eloquently (and scientifically). On the first day of spring, that's "when the Sun crosses the celestial equator going south to north." And then, on the first day of fall, that's when the Sun crosses from north to south.

Federico Respini, Unsplash

What Are the Line of Rocks at Blue Mounds State Park?

That brings us to what occurs at Blue Mounds State Park in Luverne, Minnesota.

At the state park, you'll find this line of rocks. You may not think much of it if you happened upon it, right?

But here's the cool thing that happens: On the first day of spring and the first day of fall, that line of rocks, called the equinoctial rock alignment, lines up perfectly with the sun rising and setting.

It's quite amazing and picturesque!

Larry Paulson, It's a Minnesota Thing Facebook Group

The line of rocks at Blue Mounds State Park in Minnesota perfectly aligns with the sunset.

The Blue Mounds State Park Wikipedia site says that the 1,250-foot-long rock alignment was made by the Plains Indians back in the day. They did it to mark where the sun rises and sets at the spring and autumn equinoxes. So it acted as a calendar in a way.

Today, the park keeps it preserved so we can all enjoy the amazing views.

This year, the spring equinox will be on Thursday, March 20th, 2025, so make your plans to be at Blue Mounds State Park to check it out!