“Here we go,” says my fiancé, Jason, as we scramble up a crushed basalt embankment. I glance up to see his black and orange running shoes bounding ahead, pulled forward by our sprite one-year-old vizsla, Welly. I barely take note of the steep ascent as the trail weaves us around boulders and downed maple and basswood trees. It’s cool for a June morning and we’ve been running since sunup, sneaking in plenty of breaks to take in the scenery.

This is Interstate State Park in St. Croix Falls, Wis., just across the river from Taylors Falls, a 50-mile drive from Minneapolis. A 1,330-acre park, this land is home to 12 trails that total about 9 miles. That might sound modest to the avid trail runner, but one must also consider the quad-burning possibilities: This is where the 1,200-mile Ice Age Trail begins.

Not unlike the Appalachian Trail, this partly finished public greenway follows the terminal moraine of the last glacier, showcasing the incredible landscapes left behind. Today’s mountain glaciers have nothing on the Wisconsin Glacial Episode and evidence of the existence of these massive ice sheets is quite stunning in the Badger State.

As we navigate the half-mile loop, known as the Pothole Trail, we come across a sign that reads “Western Terminus.” Standing at the top of a 200-foot gorge, the rock to which the sign is affixed is actually a glacial erratic, or a nonnative boulder that was picked up by the glacier probably hundreds of miles away and left here to rest. This is the trail’s western bookend, which from here travels eastward and then south, before hooking northeast to the eastern terminus all the way across the state in Potawatomi State Park, along the Door Peninsula.

Below is The Dalles of the St. Croix, a spectacular basalt gorge where the roaring river reaches depths of 70 feet. Welly insists we pause so she can supervise a pair of rock climbers making their way up the cliff face. Jason rests his heel on a nearby rock to stretch a tight hamstring, while I offer Welly some water and take a sip from my Camelback. The best part of trail running is that you can see more than you could hiking, even if you stop occasionally to take it all in.

About 1.1 billion years ago, volcanic eruptions along the Midcontinent Rift System dispatched lava flows, which eventually gushed into this region and formed the hard basalt we’re now standing on. In more recent history, about 70,000 years ago, the last of the glacial advances and retreats began, with the southernmost edge of that monstrous sheet of ice reaching Wisconsin. With the final melting of the glacier around 10,000 years ago, torrents of glacial meltwater charged through The Dalles of the St. Croix with astounding force as it flowed northward, carving out this landscape.

Today, an excursion boat floats along the rock walls with tourists hanging over the sides snapping pictures. As we turn to finish the loop, we notice one of the geological oddities this region is known for and for which the trail is named: glacial potholes. These cylindrical holes were created when the glacial waters whipped up whirlpools of sand and small rocks, literally drilling holes right into the basalt. Here lies the greatest concentration of these peculiar perforations — over 100 of them — some on the Minnesota side as wide as 10 feet and as deep as 60 feet.

John Muir, the Scottish-born naturalist and author, known as the “Father of the National Parks,” grew up on a farm not far from here. He once wrote, “Glaciers … crushed and ground and wore away the rocks in their march, making vast beds of soil, and at the same time developed and fashioned the landscapes into the delightful variety of hill and dale and lordly mountain that mortals call beauty.”

The awesomeness of it all is not lost on us as we follow Welly’s lead onto the next trail. She doesn’t seem fazed by the craggy climbs and trots with ease on the soft, earthy sections as we work to keep up. As a result of the short loops, we are able to mix and match distances and terrain throughout the morning.

South of the potholes, the Skyline Nature and Meadow Valley Trails, which are also part of the Ice Age Trail, are marked by rocky staircases and crushed basalt that make way for a spongy corridor that takes us through boulder graveyards alight with vegetation. On the swampy, wooded trails, we don’t dare slow down for fear the mosquitoes will begin to harvest.

Before jogging back to the car, we traverse the less technical trails around Lake O’ The Dalles, which was hollowed out by the rushing glacial waters as they left this land. Running past teenagers lounging on the beach and children who have abandoned their fishing poles to examine an expired and bloated snapping turtle, we kick off our shoes as we arrive at the car.

Welly tries to pull us toward the next trail, protesting the end of our run. As soon as she hops in the back seat and closes her eyes, she doesn’t stir again until we’re rolling over the 35W bridge on our way home.

Mackenzie Lobby is a local freelance writer and photographer with a master’s in kinesiology from the University of Minnesota. She has run 10 marathons and is a USATF-certified coach. Check out her website at mackenzielobby.com.