When freezing temps descend slow and steady on the Straits of Mackinac and winter conditions are just right, a forest of icy blue shards sets a surreal scene. Here’s how to see this stunning phenomenon and tips to make a day of it.

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You’ve likely seen images on social media or on the news of Northern Michigan’s blue ice: thick crystals jutting upward, the formations jagged and glacier-like in color, the majestic Mackinac Bridge in the distance. Professional and amateur photographers alike flock to the Straits as word gets out about this fleeting and fickle natural phenomenon. Still, nothing quite captures the eerie wonder of seeing this spectacle up close. A chance to experience it in person is worth it, demanding we watch, wonder and understand the natural forces that align to gift it to us. 

Blue ice shards under a bridge

Photo by Kim Mettler

The Science Behind The Blue Ice

According to the U.S. Geological Survey, ice appears blue when the red (long wavelengths) part of white light is absorbed by ice, and the blue (short wavelengths) light is transmitted and scattered. The longer the path light travels in ice, the bluer it appears. To further understand why ice in the Straits of Mackinac and other spots in the Great Lakes region sometimes appears blue, we turned to Will H. Cantrell, Ph.D., a physics professor at Michigan Technological University, where he and his students research why water in the Earth’s atmosphere condenses into cloud droplets, when and where this happens, and why that water sometimes freezes. One important condition for blue ice to occur is freezing temperatures that stick around long enough for a body of water to freeze and thicken slowly, Cantrell explains. “By freezing slowly, it makes a nice, clear crystal.”

Why We See The Blue Hue

Thick ice crystals with few bubbles or particles inside allow light to penetrate farther into the ice without scattering and before reflecting back. This is similar to what happens when we look into a vast, deep body of water like a Great Lake or ocean and see a deep blue hue versus the clear color of a much smaller amount in, say, a glass of water, Cantrell says.

Thick ice can transform into shards as the ice breaks up and forms ridges. “You might have a windstorm and the wind will move the different plates of ice on the lake around and they run up against each other and break,” he explains. “It’s not like they just butt up against each other and stop—one will ride up and break it, causing a ridge.”

Looking through these shards of ice, we see blue because the pathway of the light is long enough. “It’s not being scattered because it’s this nice, clear pristine ice that formed on the underside. And so, when the light transmits through that, the crystal is absorbing the red and yellow parts of the visible part of the spectrum and what you see is blue.”

Blue ice under bridge

Photo by Kim Mettler

Photography Tips From A Pro

Kim Mettler of Michigan Barefoot Memories Photography has taken stunning photos of blue ice at the Straits. After Mettler captured the phenomenon in 2018, both CNN and The Weather Channel shared her images.

Here are her tips for taking awe-inspiring photos and making the most of your blue-ice adventure:

1. Consider going at the beginning or end of the day, when the sun isn’t the brightest. “I’ve mostly done sunset because I wanted to get more color—it’s a more dynamic image if you get some pinks in the sky.”

2. Make sure the Mackinac Bridge is in the background of your shot—and don’t be afraid to include people in your photos, too. “Having people in the image doesn’t hurt—it shows the grandness of it.”

Colorful skies overlooking blue ice

Photo by Kim Mettler

3. Snap photos from your knees, or even your belly. “A low angle is always great, because you have these shards that shoot up and you’re seeing the variations in the blue. When you get lower, you can see that, versus standing up and shooting down at it. You’ll get more sky, more bridge.”

4. Stay safe! Shoe traction is always important when walking along an icy shoreline, and don’t venture out too far. “Even if you see tracks out there, it may not be safe. Having a healthy respect for the Straits is super important.” Be sure to wear weather-appropriate clothing, too. Think layers.

Colorful sunset overlooking blue ice

Photo by Kim Mettler

Where to See Blue Ice in Northern Michigan & How to Make a Day of It

Since blue ice is both gorgeous and fleeting, we recommend making plans for a Mackinaw City visit when winter is at its coldest. Follow local photographers on social media who will tip you off if the phenomenon occurs.

The best spot to view glittering blue ice up close is Mackinaw City’s Alexander Henry Park, located at the northern end of Henry Street next to Colonial Michilimackinac on Lake Huron. This park also offers amazing views of the Mackinac Bridge, Old Mackinac Point Lighthouse and Mackinac Island.

Where To Grab A Bite

Pre-adventure, stop by Pancake Chef, one of the oldest restaurants in Mackinaw City. Fuel up with banana or pumpkin pancakes (a “brunch after 11 a.m.” menu is available, too). For a meal later in the day, check out Keyhole Bar & Grill, a local favorite that’s decorated with a collection of 25,000 keys and locks—they completely cover the bars, tables and walls. Try the Bushel of Potatoes (French fries!) and original broiled whitefish.

Where To Explore Next

Cross the Mighty Mac and head five miles north of St. Ignace for a picturesque winter hike at the North Country Trail’s Castle Rock Trailhead. This pathway winds through the forest for miles, so use the map at the trailhead to determine an out-and-back route to your liking, and bring snowshoes.

Heather Johnson Durocher writes from Traverse City, where she lives with her husband Joe and their three kids. She is the founder of the travel and active lifestyle site MichiganRunnerGirl.com.

Kim Mettler Is a Northern Michigan-based commercial, lifestyle and fine art photographer. Follow her on Instagram @Michiganbarefoot.

Photo(s) by Kim Mettler