Ice racing is the most thrilling, insane sport you've never heard of

The sport of "Ice Racing" is exactly what it sounds like - cars, mostly old sedans, slipping, sliding, and bumping into each other on ice, racing for the finish line at 80 to 90 MPH. It's like NASCAR, except a little slower, and on a rock-solid frozen lake.

Husband and wife photography team Jenn Ackerman and Tim Gruber discovered the sport while working on a project documenting the winter season in Minnesota. They spotted a makeshift, handmade sign that read "Ice Racing" on the side of the road, and knew they had to follow their curiosity.

Ackerman and Gruber describe the scene they discovered during their first ice race experience: "White snow on a frozen lake with an array of colorful cars zipping by kicking up snow dust is definitely something that screams to be photographed."

Ahead, 12 images that show this seasonal, underground sport.