From the record
“The Louis Hultgren House and Sand Pit in Kerrick, Minnesota in Pine County, Minnesota, was listed on the National Register of Historic Places in 1980. In the early 1890s the site was discovered by railroad worker Louis Hultgren, who was born in Sweden in 1863 and immigrated to Pine County in 1888.”
Wikipedia article Louis Hultgren House and Sand Pit, CC BY-SA 4.0.
One of 22 National Register listings published here for Pine County · listed in 1980 · category: Building · built in 1896.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service