Two months after it was placed on the State Register of Historic Places, a Sturgeon Bay home has now received national notoriety. Earlier this month, the National Park Service listed the Dr. Joseph and Olivia Soper House as one of its latest National Register of Historic Places entries. Located on 5th Avenue in Sturgeon Bay, the over 140-year-old Italianate home was added to the register because it is the only residential structure made with Frear artificial stone. According to the Wisconsin Historical Society, the artificial stone was manufactured in Door County by Giles Kirtland, a former superintendent at the Frear Stone Manufacturing Company in Chicago, who purchased the rights to manufacture and sell the product in Sturgeon Bay. Frear stone was used at the Soper House for the block veneer, the drip course above the foundation, window sills, and decorative hoods over the windows, though much of it was replaced with more modern concrete forms a few years later. More than 70 properties in Door County are on the National Register of Historic Places. Excluding shipwrecks, the most recent county-based listing was the Potawatomi State Park Observation Tower in 2021.