 It was later used as a smith shop; an addition was constructed in 1904.The roundhouse is built of coursed mine rock masonry in the shape of a semicircle with a turntable in the center.The original structure, built in 1888 to service locomotives for the Hecla and Torch Lake Railroad, ran approximately 170 degrees around the turntable, and had twelve train stalls ranging from deep on the south end and deep on the north.